It's crazy to me that people are projecting Daichi's personality upon the author. He's a character...he's written in his own way, to have his own values.
The author also wrote about a badass lesbian, but somehow no accusations that the author is unusually progressive?
The idea is simply that Daichi follows chivalrous principles; he represents a certain ideal of not taking these things lightly. This is not an uncommon character trope, and it's weird that people are flipping out about it here.
This is a cute manga about a somewhat unconventional relationship...it's not about fanservice. Just enjoy it for what it is.