But damn let them be happy if they wanna wait???

You can read my main post. I'm not against waiting till marriage at all. However, for couples who wait, it's essential to actually communicate about their potential sex life and also talk about possible worst case scenarios.

Like, nothing like scaring a couple and saying they’ll be incompatible after marriage like saying she could be gay or asexual.

This isn't "scaring" them, it's simply pointing out a possible future. There are unfortunately tons of couples from various backgrounds that end up having issues later on. Marriage isn't an easy fix and many hang ups people have around sex often just get worse.