Honestly the storage isn't that unbelievable. Not because of the source it's coming from I don't believe in rumors. Going by what I know though is Nintendo and Xbox have a healthy relationship right now. Nintendo wants more games on the platform and Xbox wants to sell more games (obviously). Making the ports as simple as possible would require NVMe. This is purely speculation on my part but it makes sense to me. Plus people complain but statistics will probably tell you outside of places like Japan and maybe China, UK nobody cares about battery life being astronomical. Most of us will have outlets even when traveling. If they pull 2 1/2 to 3 hours of battery with that kind of horsepower they have a winner. Sure it sucks for that minority that does care but it's all about numbers.
A more restrained set of alleged Nintendo Switch 2 specs have been posted just in time to counter a rather outlandish claim recently made elsewhere on social media. While the latter involves T254 speculation that was likely inspired by perceived disappointment in the Switch 2 likely coming with the T239 chip, the former specs have been called the "most accurate" by the poster.