Is it really bad to visit Japan in August as people say it is?

will be leaving in a few days to visit japan for a little over a week. i’ve been doing quick searches and people keep saying summer in japan is horrible and there’s too many people coming over (in August specifically).

i absolutely don’t mind the heat (im from asia too) im all used to it, but the crowd? is it true japan gets crowded during these times? how bad is it? thanks a lot in advance!

edit: we will be staying in central Osaka!