Yes, you don’t have to worry as long as you don’t boot up windows and let it install the update.
This is not the first time they break dual boots by touching the partitions, but this is the first time they deliberately break it (that I know of). I always had windows on its own drive because of that. If you don’t use windows a lot then I would suggest to do the same. You have to change to windows through bios but it isn’t that much more work.
If your boss is great than you scored big. It is hard to find an understanding boss. Especially if he takes the time to mentor you. Most ppl do not have time to teach their juniors. See this as an investment for the future you. I think it sounds stupid to quit because of one reason if everything else is great. But if working from home weights more than anything else then yes you should switch.
We got the “order” to work at least at the office 2 days a week two weeks ago because the community we had has been lost. But so far have I only seen the same ppl who was at work before the “order” (I have been at work twice a week because of a project so I can tell if there is any difference) so yeah, I think most just yearn for how it was. And in the big schema of things will this only be x years or even only months of your 80-90 year old life.
I assume most are angry because they don’t get a good logical reason to why, because there are none, it is all about feelings, like community, showing customers their employees, or feeling in control because you can see and talk to ppl about what they do and if they need help. It can also be less pleasant reasons that most have already stated.
You are the only one who can make a decision for yourself. Remember that you can switch if need be.