Because, sex scenes in 1st person aren't as good as sex scenes in 3rd person. And, if the first time you see the MC is a sex scene, it's too jarring. Better to get you used to what he looks like early so that you can focus on the important stuff when that happens.
As for how he looks, beauty is definitely in the eye of the beholder. I don't think I've heard consensus on any of the large number of models Mortze has done. Some of the most attractive get a "meh" from various people. And some of the most "typical person" ones have hardcore fans. Tastes vary.
Tlaero