I dont really get the hate here. The move is fine. I'd even call it a good thing.
Yes, they broke up for a day purely because of his feelings, but to say it was for his ego isnt really fair. He wanted to restart, to properly start a relationship not just because he got confessed to by a good-looking girl, but because he has grown to like her as a person and wants to learn more about her. He didn't want their relationship tainted by a misunderstanding or desperation, but have it start proper by genuine feelings for one another.
Personally, I think thats rather sweet. Is it arbitrary? Sure, but love is a matter of emotions, so what are you doing blaming him for properly working through emotions?
Its also cringy as all hell, but theyre kids, theyre supposed to be cringy.