Mr Weasley is seen as a weird oddball for engaging in studying muggle technology. The wizarding world sees it all as a bunch of pointless nonsense that muggles have to go through just because they don’t have magic. Clever in its own way, but utterly futile.

Why spend hundreds of people’s effort, lots of money and enormous amounts of time using a vehicle to go somewhere when you can hop in a fireplace and think about where you want to go, or simply apparate there?

Why carry a complicated muggle weapon around and spend time and effort learning how to use it well, when you can kill someone with two words you’ve known since you were a child?

Voldemort isn’t just protected by being a powerful wizard, he’s also protected by the bully’s standard protections of surrounding themselves with sycophants who unquestioningly support them (by ruthlessly punishing people who question their authority), having no moral hesitancy whatsoever and avoiding like the plague fair fights wherever there’s a chance they’d not win.

So because of Voldemort’s followers who will turn up in an instant and his horcruxes, you have to be prepared to sacrifice your life to have a chance of opposing him openly, which is of course what Lily Potter did.