I'm not really sure how I feel about it. It won't be a problem for me now personally, but as a kid, I wasn't allowed to set up any of my devices to connect to the internet, meaning I would've missed out on holidays if they had had this system then. But also, that was back when even at home, you were limited to a few GB, so my parents probably also didn't want me to use up all the internet for that month. I don't know if parents still might enforce similar restrictions for other reasons now, besides maybe not knowing that they can just set up parental controls.
Honestly, though, I don't really get why they're doing it. They seem to be okay with time travelling, so suddenly restricting it seems weird to me, and seeing as they already delayed the game by nearly a year, it'd be odd if they hadn't finished the holidays. Maybe they're a bigger thing this time, or they really are against time travelling (although honestly, the holiday furniture was never very popular in online trading, except for the Flower Day stuff). Maybe we'll figure it out once the game releases.