It's near the end of the quarter and holidays tends to be less productive time for employees with many taking extra time off anyway. Even with the very generous severance is still makes sense to announce these layoffs before some of the least productive times.
Also personally, I think I'd rather know about being laid off before going into the new year.
Yeah, it's nicer to know you're on severance going into Christmas so you can tighten the belt than find out you don't have a job coming out with bills coming due.
January 1st would be calendar year though and not necessarily the fiscal year. The fiscal year can start and end any month the calendar year a company chooses. The fiscal year often does not correspond to the calendar year. See:
As soon as the economy recovers, doing these kinds of layoffs will be terrible for the companies reputation. Right now, it’s more like “who can blame them, everyone is doing it”.
Depending on your jurisdiction, most countries or states require companies to treat PTO as cash and pay it out upon leaving the company. One reason why unlimited PTO is so popular, no need to pay anything out at the end.
Also personally, I think I'd rather know about being laid off before going into the new year.