He says it himself right after, Kuroko reacts that way because he knows how it feels to stop loving basketball and to almost quit because of it.
But I think he's also probably wondering how many teams and players quit basketball after a crushing loss to Teiko? If Seiho was enough to break his senpais' spirits, Teiko must have destroyed the spirit of so many players Kuroko had no idea about.
He knows about Ogiwara but the situation was a little different, getting whipped didn't demoralized Ogiwara, he never gave up until the very end and he wouldn't have stopped playing basketball because of a defeat. He quit because the GoM toyed with them with their 111-11.
“Having doubts about something you love can be painful” is something that resonates very strongly with me, it’s truly a devastating feeling.
Even though Himuro's harshness towards Kagami was related to basketball, Kagami still has a clear mind about it. He knows the problem isn't basketball itself, so he will never hate basketball because of that.














