I will say this post isn't completely true. Denuvo (on pc) requires online checks but from what I've experienced it's typically every 2-4 weeks. I've played persona 4 and 5 on my steam deck without internet just fine.
even when I'm home, my switch is in airplane mode unless I'm actively playing online. it's crazy how often some games try to phone home, never realized until I got into this habit and started seeing the "please turn off airplane mode" popup
I don't think it really has much to do with DRM. It's practically well known at this point that consoles are easy to pirate through emulation. Especially with the constant day 1 emulation articles
So just a roundabout way to keep people from emulating games? People are gonna figure out how to relate your games. We took many years but we can finally emulate Banjo Tooie. Good games sell well and don't lose really to piracy, bad (lazily made) games deserve to be pirated