I keep standing on the same soapbox, I think it's nutso to pay high dollar for such high mileage. the used market is crazy right now.
by 194k miles there is so much that needed to be replaced and even if it was replaced, what was it replaced with? was it done correct? I don't care how good the engine is it is still wrapped around things that wear out. Plastic on the dash, hinges in the glove box, seat wear, wiring in the engine bay being heat cycled, bushings, etc etc etc. these are all things that have nothing to do with a reliable engine, but do have a lot to do with the how the truck moves down the road.
approaching 50k on my 2018 and so far so good, not 1 issue so far. emissions have gotten a lot better, Def is cheap compared to other things we spend on the trucks. I think I have put ~30 gallons of def in so far.
This isn't to say everyone should go new, but I think signficant thought should go into our preconceived notion of "new is bad because x,y,z"