Wouldn't be speaking for everyone really.
I know some may not be into things like this, but there's also other people that are. Luckily no one is forced to participate. Don't think the tab is all that intrusive as you can see it, since you can close and open it.
Less they just add it instead to the little bar in the far left corner so you can click it to open it up and back like the reapers events so it doesn't look so intrusive. (don't think it is it is a pretty small tab, but that's me.) Personally haven't had any problems with the last event, of course this can vary from person to person as experiences will be different and hopefully they can improve on that with events not ending properly or not registering.
For what it is? I like it. Nothing too overly complicated to be getting the items since it is the sims.
Doesn't force any playstyle, since again you don't gotta do it, plus I don't think there's anything wrong with limited events. It's nothing new, same with incentive for preorder items where you get said item if you preorder it in said time. Though the difference is you're still able to get these items via gallery by just downloading it to unlock it when someone uploads it. So, it's not like you're completely locked out of it ad need no mod to do so.