They all do that, even those who intend to resign deny it until the day it happens.

Ishiba doesn’t have any big scandals currently, so I see less public outrage directed at him in the news and it feels more like infighting within the LDP (just my impression). Of course losing so many seats in the election is a cause for resignation but I’m not sure anybody who replaces him will be able to quell the public’s discontent either.