I'm not sure anything 'just works'. I have an Ender 3 S1 with autoleveling. I still have to adjust 4 knobs while getting under the print head with a feeler gauge. It's absolutely maddening. I need to do this with every print. If I don't touch the thing for a few months it's really bad. If you don't get it right it will gauge your printing surface or alternatively rip your piece apart as it prints. Then you need to know about bed temperature, nozzle temperature, and a hundred other things. Then what types of filament work best with certain bed types. I wish I never got it.
I've never any sort of pre-print processing/calibration on my Prusa MK4(S), other than cleaning the build plate. This sort of hand-holding really isn't required anymore on the modern printers.
Slicers also come with presets for different filaments these days, which generally do a reasonable job and knowing about temps & co is largely optional to getting going.
There are lemons, but generally Prusa is excellent for that, yes. My Mk3s has been working reliably for six years. The only problem I ever had with it was an error I made in assembly. I can go six months without using it or use it every day all day for a week and it prints reliably either way.
Yes, Prusa and Bambu should both be reliable. I've been printing with Prusa MK3s for a couple of years without any problems. I think I've had just one failed print and it was because there was dust on the plate and I needed to wash it with water and soap.
Yeah, they're work horses. I've printed for thousands of hours on my MK4(S) now, and it's still going strong. I've had no issues at all. Similar experiences around me.
