I noticed round holes in my lawn over the last few days. My neighbor thinks they are snake holes. He is just taking a wild guess per his own admission. I am in Maryland and we have had a lot of rain in the last few days.
Snakes use old tunnels of moles and shrews and gophers. There is no sign of digging for this hole so it just might be a snake. Snakes are usually totally beneficial and take care of mice, rats, voles that might do damage to your plants. The snakes are not going to be a problem.
Moles and gophers aren't a problem.
But your lawn could us some help. What time of year is it where you live? Where do you live?
Yes moles do do harm to grass The tunnels and the dirt that is left behind from digging covers grass which kills it. If you have spent a lot of money on keeping your lawn nice and presentable this is a waste of your money. Getting rid of moles is an option to keep your yard from looking mangled. if you're concerned about aeration then have a company do aeration once a year typically at the end of the fall but we got rid of our moles with a critter control company and it lasted for a couple of years.
It is most likely soil-subsidence. You can find a picture that looks exactly like yours on this website: https://www.walterreeves.com/insects-and-animals/diagnosing-holes-in-the-yard/
What differentiates subsidence holes & critter holes is the presence of loose dirt - which occurs with critter made holes.