Switch 1 is already nothing like Wii, Gamecube and N64 in that it's still getting plenty of games post-replacement while support for those three died off before their successor even hits the shelves.

Given how long it will take for most of the userbase to upgrade even if Switch 2 sells well, and that smaller games are continuing to make their way to Switch 1, I don't see it dying off in terms of being an active platform for a long time to come.

This is the first time I haven't bought a pokemon game and I have no desire to do so. I didn't feel anything while watching the trailers and some streams.

Leaving aside the graphics which I find hideous, is the gameplay any good? For those who have played it, how do you find it?

Pokémon Legends Z-A sees biggest retail launch of year. This seems like a very successful launch, outdoing even Ghost of Yotēi in terms of retail figures. Still a far cry from previous entries, but solid nonetheless.

It sold 89k first week in Spain. Legends Arceus did 140k on a much smaller install base. I wouldn't say it's very successful at all for the series. A similar big decline on Arceus that it saw in the UK. Japan will be interesting to see if that follows the same trend or if it can get closer/exceed Arceus launch.

Honestly this is not what I was expecting from Legends Z-A at all so far. Maybe it can turn things around in the holiday but my prediction this would outsell Arceus isn't looking too good right now.

Are the Spain and UK sales including NS1+NS2? Very curious to see what Nintendo reports as they will also include digital.

Yes. For Spain FW:

Arceus (Switch 1) - 140k
Z-A (Switch 1) - 53k
Z-A (Switch 2) - 36k

I think its kind of impossible for a full fledged pokemon game to not have a successful launch but maybe it didn't meet expectations.  I would add though that I don't think Nintendo expectations are as high some people think. Not all games/sequels/spinoffs are equal and this looks way less ambitious and probably cost less to develop than archeus. 

Still hope it nudges them in acknolwledging preferences in regards to environment, presentation quality etc

It will be extremely profitable no matter what, we know the budgets of the games from the leak and they are incredibly low. Relative to other games in the series it could certainly end up a sale disappointment regardless of if it makes a gazillion in profit or not though. It's all relative. For a pokemon game it may be "unsuccessful" even if for pretty much any other game series it would be a great success. Just as GTA VI selling 20m lifetime would be a disaster, which is an unthinkable thing to say for any other game.

Oh I'm speaking in Pokemon terms. 

One of my suspicions on why this game looks so basic is that they want to use it as an experiment for combat evolution and minimised effort elsewhere.  Meanwhile the team is dedicating their actual time the next-gen entry. This could literally have half the development cost of Arceus and internal expectation may reflect that. As I said, not all sequels or spinoffs are equal in terms of cost or subsequent expectations, so just something to bare in mind. 

As per the leaks, the development cost for Arceus was 2.18B Yen and their internal estimate for Z-A at the time of the leaked data (2024?) was 2B Yen. ($14.3m vs $13.2m). So if the final development cost was as they estimated it was cheaper to make but by less than 10%. It's also worth noting that Z-A at the time of the leak was internally expected to launch in 2024 so the budget could have easily exceeded their estimates and ended up costing more to make than Arceus.

But as I said before the dev budgets are so dramatically low they'll make a crap ton in profit even if it sells less than arceus. Even with a very large marketing budget they'd be breaking even by 3m sales.