They are 4 stroke, but they put small mufflers on them. Electric lawnmowers make a lot of noise, too. Not as bad as the droning of a 4 stroke at full throttle, but still noisy.
I long for the day we ban lawns. Do that, and lawn mowers and weed whackers would vanish overnight.
My neighbor started a new lawn. The amount of water he has been using during the last few weeks with this automated sprinkling system is staggering. There should be a more natural and robust solution, some mix of weeds and small flowers that's also walkable, but also gives bees and other insects a place to live.
I'm big into water wise landscaping, but there aren't really any species of groundcover that are both highly tolerant of foot traffic and also very water thrifty.
Mostly shaded bluegrass actually uses less water than full sun buffalograss. (And buffalograss can't handle shade) So tree plus grass is actually pretty water thrifty as well as keeping your house cool...
I long for the day we ban lawns. Do that, and lawn mowers and weed whackers would vanish overnight.