"Fast-selling console in history" is to Switch 2 sales concerns what "Publisher of the Year" was to complaints about XBOX's first party.
While I think history somewhat bears this out, I don't think the future will. Both of these companies are saturating their current market demographics, but neither is about to quit there. We already saw with Switch 2 a shift in messaging towards enthusiast gamers - championing cutting edge tech and placing big-name third-party games like Cyberpunk and Elden Ring at the forefront of launch messaging. Call of Duty and Madden might not be topping Switch 2 sales, but in order to grow they do need to capture more of that demographic.
Likewise, there's been visible audience broadening from PlayStation in the direction of Nintendo with titles like Astro Bot and LEGO Horizon Adventures. The latter even appeared on Switch itself, which is very telling. Right now, this is all nascent activity, but it signals the reality that even if they aren't in direct competition right now, there's a strong chance they could be in future.
Taken in that context, some of Switch's success might be attributable to the fact that Sony and MS were too busy fighting each other to bother fighting them. Being that XBOX has now thrown the towel, there's only two real contenders still in the ring...