I think the bigger problem for me is that it interacts very weakly with the rest of the game. So while there's games that I might never build an aqueduct, or even ones where I skip theatres practically entirely, there's always reminders around - you see the great artist points, you see policy cards, military engineers have charges, etc...
But Preserves, just, don't. There's no policy cards related to them. There's no tech or civic boosts that need them. I mean, I guess Reyna indirectly interacts with them in that her forestry management policy is absolutely amazing with them. They don't give you any yield that you can't otherwise get from something else. So you really can just totally ignore them, and it basically never hurts.
It also suffers in that since it unlocks early, you run the risk of finding some late resource and ruining it. Like in my last game, had a preserve setup going with 2 cities actually, and a coal tile popped in between the 2 preserves. Thankfully I had coal elsewhere, because it would have basically destroyed the whole setup throwing down a coal mine there - would have cost me 4 food, 4 culture, 4 faith, plus probably would have taken the neighbour tiles down below breathtaking too. I mean, welcome to the real world where you have to decide if you want coal mines or a natural park, but still...