Haven't had any issues so far with 3-4 hours of play.
Horror stories on Reddit this morning. Multiple people reporting crashing errors. Who knows. Just figured I'd put a PSA out. I love the game and will be buying it again for my Switch, but Switch is getting notorious for these release day problems. I was looking forward to My Time in Portia and that release was BRUTAL.
I got a year of Switch Online when I bought Mario Maker 2 and got a code in my email for some Splatoon 2 bonus gear. I don't have the game nor am I interested in getting it so if anybody wants it let me know. It's only compatible with the EU version though.