Alright, we're starting to conflate two separate issues here. Regarding the Asylum specifically, no, it should not provide population if it's also being called 'abandoned'. However, it could have gone the other way and been renamed instead in order to keep the population - either way would have been fine with me, though I obviously prefer the route they took.
The other issue, which you're kinda mixing in with the above, is that event prizes are consistently providing population. There is no balance with event buildings right now, which is a problem for long-time players. Doesn't matter what age they're in, because the longer they play, the more event buildings they're going to get and the more their population is going to spiral out of control unless things change. This has nothing to do with age and everything to do with the amount of event buildings in your city.
Let me put it to you like this, since you're entirely focused on this one event still: Imagine a city that's already got the happiness GBs built. Now, fill the rest of the city space with Asylums that provide population. This is essentially what folks like myself are talking about: Cities filled with event buildings, not necessarily a single building by itself. My city contains prizes from multiple events, all of them providing population because that's what Inno decided to slap on them. Regardless of what age I'm in, I'm going to have these same event prizes and I'm going to have the same population issue because, again, that's what Inno decided to slap on them. If I was a player in SAM who had no event buildings in my city, yeah, everything looks awesome because I'm replacing ordinary buildings from the research tree with them. However, anyone who's been playing events for the past couple years is going to have population well in excess of what they want (or need) no matter what age they're in.
I think I've said this before, but what it really boils down to is that when you look at events as a whole, there's too much population being offered. I want to see less population coming from events. That could lead to the assumption that I want to see more happiness, which I do, but it's possible to have a great event prize that provides neither one of these things and I'm more interested in simply seeing less population.