1. Currently bitcoin is adopted by ElSalvador and Namibia and I think the adoption is growing.
But we cannot really say that in the next 2 years the adoption will drastically increase. It will take its time.

2. Yes, I think more companies will be involved with crypto. Now that there are rumors that google will accept crypto for its cloud services.
May be this will encourage other companies to accept crypto as well.

3. Ofcourse

4. Need a bull run for increase in number of users.

5. I think bitcoin halving will be a major event to trigger the next bull run.