The primary failure I've observed in washing machines that get a lot of use is the drain pumps which are probably similarly (un)reliable across designs (we only have front loaders so not sure).
I've had to replace the pump on a cheap amana NFW7200TW. Being a cheaper model it does not have a coin trap and the thin plastic vanes shattered (the coin rested fully intact). The pump had two part numbers, one a Samsung and another a Whirlpool (?). The point that may be interesting here is that when I asked at the part store for the whirlpool p/n they brought me the box at one price, and when I asked for the Samsung one they brought me the exact same box at a price almost $30 less. I didnt know they did SKUs like that, nor do I know how they account for it.
Clutches can wear out too, everything will still work but the washer won't really agitate well.
Probably true, I don't think any of our machines have clutch.