Parques Reunidos, your visitor and employee numbers may be impressive, but the trends are not looking good. The business model seems to be to purchase parks that are "readily developed", and then cut all costs to the bone, giving back as little as possible while the park slowly ages and things gradually become worse and worse.
In my home park, TusenFryd, the signs of under-investment are clearly visible. New attractions are added at a steadily slower pace, queue times keep going up (whose idea was it to man a 40-seat Giant Discovery with a single staff member, giving it a dispatch time interval of around 10 minutes?), the food is regularly ranked the worst in the country by travel guides, the buildings are screaming for a new lick of paint, old attractions are scrapped without a replacement, and visitor numbers are down 20 % from 2006 (while other amusement attractions in the country and region have almost doubled their attendance in the meantime). The only arrow pointing up for that park is the ticket price.
But there's a whole big world of amusement parks under the Parques Reunidos umbrella. Maybe it's not so bad elsewhere? Let's tour Europe and see.
Some Googling reveals that Bonbon-Land (Denmark) currently sees around half the visitor numbers it had in 2006. This while non-PR parks in the country like Legoland Billund, Fårup Sommerland and Djurs Sommerland have seen increases of around 10-60 % in the meantime. Perhaps some of the reason is that they have added a few rollercoasters instead of removing them like Bonbon-Land has.
On to the Netherlands. Attraciepark Slagharen had around 1.5 million guests in 2011, before PR took over. In 2016, they dipped below the million, and the 2017 numbers were hardly better. Efteling, meanwhile, has gone from ~4 million to ~5 million in the same time span. Clearly Dutch people have picked up an appreciation for theme parks, but they're not going to your properties.
Bobbejaanland in Belgium? Same story. Attendance down 9% last year, if I'm reading the numbers reported by Looopings correctly. The exact numbers haven't been released, so it's hard to tell a trend, but apparently the park is struggling to stay afloat. Wikipedia's latest numbers are from 2008 and quote 740,000 visitors that year. Walibi Belgium's attendance, meanwhile seems to be relatively steady around the ~1 million mark, 1.3-1.4 if the waterpark is included.
Next would be Germany, and Movie Park... if I could find any recent numbers. Apparently, figures haven't been released in a few years, but its annual visitor record was apparently broken in 2014. I guess a statement would have been made if the record had been broken again, so let's put this one down as stagnant since 2014. Wikipedia shows that Europa Park has grown steadily since 2008, so apparently the market is there and it is growing. Granted, it's pretty hard to find historical visitor numbers for German parks in general. Hansa Park and Heide Park also seem to boast about record attendance in recent years, at least.
Great, Italy then. Mirabilandia had two million visitors in 2009. In 2016, it had 1.6 million. Gardaland, meanwhile, went from 2.8 to 3 million between 2010 and 2016. Granted, numbers appears to have been stable as another source mentions 3 million visitors in Gardaland in 2007 as well. Mirabilandia deserves extra mention as it was once the park that built Katun and iSpeed, world-class thrill coasters. Now all they're getting is inexpensive rides for children. The ambitions died not long after Parques Reunidos took over.
And then Spain. PortAventura has been nice enough to release its visitor numbers, which rose from 3.7 million in 2012 to 4.7 million in 2017. They also built several major attractions in the meantime. By contrast, Parque Warner Madrid and Parque de Atracciones de Madrid has seen one new roller coaster between them *since 2009*. I can only compare the coaster numbers as visitor numbers appear to be a closely guarded secret. Not that comparisons would be that useful, since the Spanish theme park industry was in shambles when those parks were bought by Parques Reunidos. All I can conclude is that the chain does not appear willing to develop the parks, instead relying on attractions that were built years before they took them over.
As these numbers show, visitors to European amusement parks in general have been stable or rising in the past ten years. Parques Reunidos parks, however, seem to have lost visitors all over Europe, which might explain the company policy not to release visitor figures anymore. Instead, the total visitor numbers are displayed for the whole chain, because those can be inflated by buying up new parks. The acquisition of Belantis will probably make this year's numbers look even nicer ("Up 600,000 in one year! That's a 3 % increase!"), but it says nothing about how each individual park is faring. And that is probably the intention.
So who hired those 10,000 professionals? Who built the parks that attracted twenty million people? Various previous owners. Parques Reunidos has taken over successful parks and tried to maintain the success without doing anything to uphold it. Only by cutting away those things that don't make money on paper. Why staff a restaurant with 5 people if it can technically be done with 3? Why pay good money to keep an attraction running for 5 more years if it can just be scrapped? Why build a 30 m tall coaster when one 7.5 m tall is much cheaper? Why build a coaster at all if you can hire a guy in a funny costume to do a juggling act in the parking lot? Why paint the buildings every 5 years when you can do it every 15 years? Why are your visitor numbers collapsing and your reputation suddenly the worst in the world among fans of theme parks?
Ask anybody with a bit of travel experience about who is worse than Parques Reunidos in this industry. Most will concede that for all their flaws, Six Flags is at least giving their parks new attractions. Cedar Fair builds spectacular rides when they finally decide to build them. Merlin Entertainment has a fixation on post-apocalyptic themes and shipping containers, but their parks see large-ish new attractions every few years. Some with a lot of international experience may mention Fantawild and how they build their parks 90 % complete, open them, and never let a carpenter anywhere near them again, but all in all you have to travel to China to find a less-liked theme park operator than Parques Reunidos. It seems like the chain itself is realizing this, as its home page is doing everything it can to tell investors how great it is at making money, while seriously downplaying its involvement in running amusement parks. Because the visitors are not the focus. The investors are.