I feel like it should seem obvious gas stoves create unhealthy pollution in an indoor environment.

What is less obvious and what I would personally like to know is how much pollution remains if you have a hood above your gas stove that exhausts outdoors that is operating while cooking.

some definitely does linger and most consumer kitchen hoods are not strong enough, you can get a pm2.5 meter and find out yourself... in my experience a couple hours

the craziest thing is no hood at all, if you cook once a day that stuff lingers all day unless you open a bunch of windows