I just...cannot fathom how the new version of this app went through development, testing, (focus group doesn't seem like it could have been a thing at all or you wouldn't have screwed this up so badly), etc. and NOT ONE PERSON thought removing copy/paste functionality was a bad idea. That's been an expected staple of pretty much every program for a really long time and you just...left that out?? This probably makes a pretty strong case for allowing different versions of an app to coexist simultaneously (i.e. Office 2016, Office 2019) instead of the constant-updating model that you've just proven can go horribly wrong. Whiteboard 2016, Whiteboard 2021. Not difficult. Then if the new one is well received, phase out the old one. If the new one is widely panned (where we are now) you haven't shot yourselves squarely through both feet as people can continue to use the "old" version until you have the new one where it needs to be.
Honestly, there should be some billionaires wandering around somewhere who can remind you how Microsoft made it's money in the first place.