This was a tactful announcement and a generous severance after providing a job with pay and benefits in the top 0.1% for possibly years and years.
My personal belief is that I would like to see discussion of the system that gets us to the point of mass layoffs. As rich as Zuck or Musk or whoever is, they are still close to gears in the system than orchestrators, so we should probably have a discussion about if this situation is something we could modify the system to prevent, and if we want to modify the system in that way.
Yes. Accepting responsibility is more preferable to not accepting it and blaming it on other people/things, period.
Let's say you have two leaders in this situation. #1 says "The macro economic climate is bad, so we're laying people off." #2 says "I made a mistake; this was my fault." All other things equal, I know which one I'd prefer to work with... How a leader comports themselves is just as important as their results -- especially in bad times.