If you look enough you can eventually get "lucky". I recently snagged an old Massey 7' in.. well.. I'll be honest it's not in super great shape but it is, I believe, very recoverable. But it was only $175 and it was less than 10 minutes drive away so it definitely followed me home. Most of the rust is on the bar with only a little on the lower moving bits so it's getting a periodic acetone/transmission fluid bath over the winter in anticipation of being able to pull out the bar and replace the cutters in the spring. I'm hoping with a bit of grease, new set of cutters and a couple replacement guards it'll be good to go, we'll see how it looks as I get things freed up.
For the OP's question.. There are definitely trade offs.. and some of the Korean tractors are better than others (even within a given manufacturer). I recently ordered a Branson (Tym) 5520H to be a big buddy to my little bota that should be on property next week. I also looked at a Kubota MX and a used grand L and some other used MX and M series. I'd have bought the older used grand L if the seller hadn't skeezed me out, it was objectively a smoother/nicer tractor. I also looked hard at some of the other second tier offerings and felt the 20 series Branson had relatively low complaint ratios, and generally historically "not bad" build quality (most of the complaints were things I could mostly live with). It was a cost/benefit trade off and I'll see with time if I made the right call or not.
There have definitely been missteps by the majors as well, the original Kubota
L3301 is a good example, I'd never buy one of those the DPF/engine sizing is bad and they have a lot of clogging problems. Similarly if you're looking at a used Deere 1023/1025 you better make sure the front axle has been fixed.
I also preferentially wouldn't buy a Deere at this point due to their anti-consumer stance on right-to-repair. This is both a political point and not.. I generally prefer working on my own equipment when possible because I know what's been done and I don't have to fine tooth someone else's work afterwards to make sure they didn't mess it up - yes I have trust problems, but also I've been burned by yahoos who didn't fix things right as well from shops I thought I could trust.. I suppose if you only use stuff in warranty and only go to the dealer.. but I'm a drive it until it dies person). I've also found some disturbingly loose bolts and missing parts on my little Kubota. I DID buy the bota used but the PO wasn't exactly what I'd call a mechanic so I'm 99% blaming his dealer for doing a half-assed job on servicing it...
Are you MORE likely to have problems with a second tier tractor? Possibly.. in either case I'd be looking at models a couple years old that have had more of the kinks worked out and were you can get actual in-use reviews..