People on here tend to get a bit worked up when you don't meet their definition of proper.
I just replaced the 13 year old tires on my 16' car hauler. It spent its whole life parked in nearly the same spot and didn't travel many miles or very far from home. Granted, a blowout wouldn't do much more than maybe bend the fender a little which may not be the case on a travel trailer.
The tires on the side that faced south all those years had some cracking on the sidewalls. The tires on the other side looked like new yet. I only replaced them because I needed to take it 250+ miles away with a bunch of freeway miles.
I only had to add a little air each year before use.