Bubblehead charm and shield charm? And teargas wouldn't much harm the effectiveness of a wizard who can do non-verbal casting. Unless they're in a closed space with it for a loong time without any protection.

Also, the whole "wizards don't understand muggle tech" doesn't make sense seeing how many muggleborns there are. Like honestly, Hermione wouldn't bring pencils/pens to school? Would pens not work in Hogwarts , as "muggle tech"? Pencils?

And how on Earth is it that non-muggle wizards into muggle shit can't like, visit a library or purchase an encyclopedia? They clearly interact with the muggle world, and that's not illegal, nor are muggle objects (unless you enchant them.)

The worst part is how muggle-borns can have siblings who aren't wizards and how muggle-born kids seem to not be able to keep any of the friends they had before turning 11. That or we're meant to believe 12-year olds wouldn't boast about being actually magical to their best friends on their first vacation.