it's just the obvious they think the older the more controlling
No, you're oversimplifying. But I expected that. Nobody truly wants to be told the potential pitfalls of a relationship like this.
It's not so much that a much older partner must be more controlling as much as it's likely (though of course not certain) that they are fulfilling a need to be somehow "ahead" of the younger one. A desire to be seen as more worldly, mature and wise. Like I said, very few younger women will see or admit to this dynamic (I was a bit more honest with myself than most, I think, but I still downplayed it and told myself the key parts of the relationship were entirely incidental to him being old enough to be my dad, although if that were the true, what else did he have to mark him out from a younger man?) as we all like to feel we are masters of our fate.
But it's almost inevitable. After all, there's likely to be something up if you don't have some sort of life advantage over someone 20+ years younger. Because frankly, if you're a functioning adult, you damn well should have grown in that time...and however mature you are at 25, you're not going to have 20 years on yourself.
That's not the same as being controlling or predatory, nor does it mean these relationships can't work. But it's foolish to pretend you're dating a 25 year old in a 45 year old body (who wants someone who's spent 20 years not growing?) or that you won't grow yourself as you age. Which is why I've said that a lot of women do outgrow the role.
You're a grown up, so good luck to you. As I said, no judgement from me, I've had more than one age gap relationship so I do understand the appeal (and they weren't sugar relationships). But you've asked us, so I guess you have twigged something, and you're right to be aware.