Los Angeles is an extreme case, but air pollution remains an urban problem. Emissions have been reduced, not eliminated.
It can still be a problem without being so visible as to limit your vision to less than a city block while the infirm non-hyperbolically suffocate to death.
Rental water heaters are some weird Canadian scam.
My ~70 year old water heater failed 5 years ago. I drove to the nearest hardware store, paid $700 for a new one, and installed it myself.
Comparing efficiency between electric and gas is complete nonsense. You need to compare operating cost. In my market, with very high electric prices, it’s $60/yr for gas tank, and $1,100/yr for electric tankless.