Main reason normal people do not use public transport is this attitude and police giving up on enforcing basic public order on transport. Personally I am voting against any public transport funding until all homeless/druggies are kicked off public transport (even if they are willing to pay). You have to pass certain very low behavior bar to use public transport (no intoxication, no aggression to other passengers, no smell, no shouting random things).

It's not rocket science and other countries figured out how to do it.

It's not a policing problem, it's a homelessness and mental health problem.

You'll never have enough police for regular enforcement on buses. The numbers don't add up, not even remotely.

Other countries do a better job when they're able to keep people off the streets in the first place. Which then becomes a much more complicated question about social spending and the civil liberties of mentally ill people who don't want to be institutionalized.