Those devices are bad for humans and from what I've read dogs don't actually seem to mind them very much. They are unquestionably capable of damaging human hearing, so it seems a little sociopathic to me to be suggesting them on a tinnitus forum. If you don't believe that these devices can be damaging, I recommend buying a "Scram Patrol" ultrasonic gun off of the internet for $15 and shooting yourself with it. I have done this. It was not a pleasant experience.
I moved to as close to the middle of nowhere as I'd really want to live -- the nearest house is hundreds of feet away, and there are only 1-2 other houses closer than 1/3-1/2 mile. Mostly it's very quiet, but... birds are loud, people do need to mow which can be loud, we have to mow. So, the noise I'm exposed to on a daily basis is miniscule compared to what you get in the city, but that doesn't mean it never bothers me...
There's a quote somewhere about how anyone can go to the monestary, but the true monk brings the monestary with him back into the heart of the city. I think there's a nugget in there about tinnitus and our mindstates in general... we don't always have control over our external circumstances, so we have to become the best custodians and guardians of our own internal experience that we can. Working towards self-love and self-compassion has done more for me than escapism.
All that said, if you really want to set yourself up to just be someplace quiet, then in America you are going to have to come up with some kind of financial independence. If you're comfortable around people, contributing to group welfare, and sleeping in relatively rough conditions, there may be
intentional communities that could be an option for you.
Alternately, learn how to build software using modern tooling through free classes online, get a couple small gigs building apps or websites for people to build your resume, and then find someone willing to hire you as a remote worker. I have been doing remote tech work for the past year and I hope that it may be some significant period of time before I have to go to an office again.....