Well there is a difference between having a boner because of someone's face and getting a boner because of someone's glasses...
Also he was like pursing this guy actively for months and shared classes with him. It’s not just his looks but the ML switched tunes after being hit on by the same person multiple times the second he put these glasses on. And that’s the thing about a fetish it’s reasonable for the target to feel I’m just satisfying this fantasy of yours but you can find another glasses wearing, or plus size, or some ethnic group person to satisfy that. And if he somehow he gets bit by a radioactive spider and obtains perfect vision will your love disappear.
Wait wait wait, didn't MC mainly liked our ML here because he was handsome? The mental gymnastics in BL is genuinely hilarious sometimes ༎‿༎