I agree with everything Rol said in the OP. I just want to add that the announcement of Splatoon 3 was a big signal that Nintendo doesn't need to replace their hardware anytime soon. They aren't sticking to the "one game per franchise" rule that they often do. When you take that, Arceus, and BotW2 into consideration, then you should also consider that games like XC3 will also probably release on the Switch. Mario Kart 9 is not out of the question either. They can release second iterations of any of the franchises that they've already released.
People often say that the second game doesn't increase momentum, but Switch hardware isn't going to increase momentum at this point anyway. What strong second releases do is that they keep the momentum going. Hardware sales are not going to have the brakes put on them, because the first party software pipeline is strong. This makes player enthusiasm keep going, word of mouth keeps going, and the second hand market isn't flooded with used systems. Additionally, third party developers see that Nintendo is still putting out big titles and so they feel confident about releasing their own games on the Switch. It shows that the Switch is going to be a relevant system for years to come. So these first party games are inspiring third party releases, and all of this continues to drive momentum.
Essentially, these second releases of big titles like Splatoon 3 do keep Switch momentum going, and Nintendo has not shown any signs yet that it is going to let first party development dry up anytime soon.
curl-6 bet me that PS5 + X|S sales would reach 56m before year end 2023 and he was right.
My Bet With curl-6
Switch Will Be #1 All Time
Zelda Will Outsell Mario (Achieved)
How Much Will MH Rise sell?
My Bet With Metallox