I don’t see “the bells” being what provokes Dany into being the Mad Queen and burning shyt down.
It’s really a good character moment, I think, if executed better. When she heard the surrender bells, she knew she had already won. King’s Landing was hers. She had, in that moment, gotten all that she had fought and suffered for over the seasons...the Iron Throne.
It was a deciding moment for her. Whether she would accept their surrender and be a good ruler, or whether she would be like “fukk surrender” on some “Mad Queen” shyt and give into her darker impulses like her father did.
She hesitated, but then she succumbed to the latter. It’s not that the bells triggered her. The bells gave her a choice...and due to extenuating circumstances...she made the wrong choice and gave in to impulse.