Threads like this are distressing. For years, there's been evidence that RTAC's (Roof Top Air Conditioners) were pretty long-lived.
I base this mostly on Coleman Mach units. They seem to go years and years before needing capacitors, blower motors, etc. But there weren't all that many reports of leaks or compressors.
Starting to think the manufacturers are cheapening them to get through warranty and not much more. There's been a rash of replacements lately.
My thought on these is when they need a compressor or have sprung a leak, they aren't economical to pay for repair and aren't satisfactorily repairable by a DIY. Being a tinkerer, I guess I'd look at one like described here and at least see if I could spot the source of a leak.
But, I'd have to be able to find it, be able to fix it, be able to install a charging port, be able to evacuate it, HAVE THE THE REFRIGERANT, and be able to charge it ACCURATELY. They have a very small sealed system so the charge is correspondingly small and difficult for DIY to get exactly right. Slightest bit off on a small system and it just won't work well if at all.