As mentioned, I like them and add them to every tank. But I did want to address the negatives you mentioned other hobbyist's saying
Some say they are pests. They burrow to only the first 1" of substrate, letting gas pockets develop either way.
I can't say if this is true or not, I've never dug into my substrate to find the maximum depth they will burrow. I'd reckon this is largely dependent on the substrate itself -how heavy it is, how much it compacts, etc. But the snails aren't "letting" gas pockets develop that wouldn't if they weren't in there, so that logic sounds a bit faulty to me. Gas pockets can be created over time, more will be disturbed by having snails than by not.
On top of their lack of aeration capability, they also uproot plants with delicate root systems and in the process of hanging out under the substrate they also leave their waste which over time can add up and become noxious.
I've never had a problem with them uprooting plants. Not to say they've never done it in any tank I own, but I have a lot of tanks running for a lot of years with a lot of plants and MTS. If this was a problem, I'd be dealing with it. As for their waste, they aren't consuming anything that you aren't putting in there! Even algae is brought on by nutrients we add to our tanks. And these tiny things aren't capable of producing that
much waste. When I put a handful in some 20 gallon aquariums I'm recently setting up, I was hoping for more waste. But on bare glass bottoms after weeks of algae growth, the amount of snail poop was disappointing. I think any waste accumulation would have been there with or without snails. If tanks are overfed and under-maintained, that's just an eventuality.
They over-reproduce and cause more harm in the tank than good due to their excessive collective bioload, and their shells litter the tank as past generations die, leaving more shell than substrate over time.
As has been mentioned, nothing reproduces past its resources. If there isn't too much food there will not be too many snails. As for shells, I'm trying to see how bad this can get. Have quite a few building up, I stopped picking them out several years ago. Still bet I could pick virtually all out in 20 minutes.
Whether or not to add snails to your aquarium is up to you. And I would be lying if I said they are easy to completely eradicate if for some reason you change your mind. But I do feel like most of the so-called drawbacks are using warped logic. At worst, snails don't provide a ton of upside, just a little. But I'm hard-pressed to find a downside.