I'm vers and have two sexual ideal types...
1. If I'm topping - effeminate, young, petite, girly, very slim, smooth, twinky bottoms. No interest at all in how hung they are.
2. If I'm bottoming then it's the opposite to above. Masc, tall, muscle alpha tops. Big dicks.
Dating wise, I'm a lot more open minded because other things come into play and I accept that I am a mix of the above so should expect it in others also. But seeing a very femme boy with a masculine alpha is the HOTTEST thing in the world to me. If I see it in the street or a bar I just get really turned on.
In the big UK cities I'm noticing guys be more open about actively seeking fem. It's often bi men or men that are looking for trans but say in their profile "or femme". I sort of get why if you're into trans you'd also like femme boys.
Since the beginning of time gay men have idolised femininity in men. Look at the Greeks. I think it's always been there, it's just might not have been socially acceptable. I feel like a lot of the gay rights movement focused on pushing a concept of "normal" gay men because that was the least offensive to straight people. Hopefully that is changing.