I watched a video essay on animation a couple years ago that sent me toward the Punch Out games, particularly
Super Punch Out on the Wii. I thought it was pretty damned fun (and yeah, S-tier animation work) but I wasn't good enough to beat it.
Tried one of the older games, too. Can't remember if it was the NES or SNES, but I think the latter? It was also fun, but not as impressive or engaging for me.
As for the future... I dunno that
Punch Out has a future. Like most (good) Wii games, SPO would be fantastic to play on the Switch (good lord,
Skyward Sword is ~sublime~) but that's assuming Nintendo cares, and that's usually not the case.
I think
Punch Out may also be in a similar position to
F-Zero, which Nintendo abandoned due to not wanting two competing racing series. Similarly we have Nintendo's new boxing IP in
Project ARMS, which could potentially be the "new"
Punch Out. If it was sufficiently successful, of course. And if it wasn't... then there's still no cause for optimism, I think, as it would likely be seen as a failure of "boxing game," not PA specifically, because that's how these things always seem to okay out.