If we didnt get regular updates then:
People would TT and spoil holidays like in NL
We would have to wait longer for the games release
Nintendo would not be able to put out as much content as they'd like (we would have significantly less to work with.)
The updates NOT ONLY give us the holidays but will add other features as well. Shops, trees, the town itself will have different appearances based on the holiday and time surrounding it. I imagine they will add in new dialogue and items as well for these time periods.
Free updates are NOT a bad thing. What we get out of them are things we will NOT need or theoretically be able to use right when we start the game. They do not affect initial gameplay and will not result in a loss of experiences since we do not need the features they are adding until later.
Idk. I personally dont understand why free updates are so bad when they enhance the gameplay and make everything more exciting. We wont know anyrhing until it happens, we wont have guides out months before the holiday even occurs in real time; we can go in blind and have fun.
Nintendo is just trying to give everyone a sense of not knowing what will happen and wanting to play every single day to see what will change or if there will be anything new. Reporters not being able to share anything past march 16th makes me wonder what exactly happens that is SO new and exciting we cant know about yet. The updates to prevent us from seeing holidays early makes me EXCITED to see what they come up with. Almost like opening a present; don't know exactly what's in it but excited to see regardless.