I mean you also drive a car in city limits and it is illegal to fire a gun in city limits in most places...

It is also illegal to shoot someone but we still have gun control laws.

It's legal to shoot people under certain circumstances... self defense, defense of another, performing a git merge, etc.

Possibly to lower the likelihood of people breaking the other law..

I think one of those things should be loud and one of those things should be quiet.

Suppressed firearms are still quite loud, typically 120-150dB, vs 145-175dB unsuppressed. It's enough to reduce hearing damage but still sounds like a gunshot.

The sound they make in movies couldn't be further from reality.

Try living near a range. Mandatory suppressors would be a blessing.

Depending on your state, you can perfectly get a suppressor / silencer on your gun.

You need to get a threaded barrel, $250, available online.

Then you fill out paperwork, pay the ATF $200, wait, and then you'll get permission to buy one.