I created new account for my wife (before I was aware of issue) - it switched to V2 after around one month.
Now I created new one for me, but it is still on V1 - I left it unused, to see how it goes.
However, my main account is used for years, there is plenty of stuff bought there on Store and XBox, and migration will not be simple for me.
Yes, that's how they get us. I heard about sharepoint but I never looked into the product. I wonder if it's possible to force migration by trying it or by taking a month subscription, then cancelling shortly after.
Personally, I just segregated the old and the new stuff. Stopped using shares. I will eventually need to format my PC and install windows again, something I am overdue for years. I'll use the V2 accounts for that when I do that even if that means wasting one "good account", which is the payer.
It's interesting that my payer is the only account not migrated. Maybe this issue IS intentional since most of us are likely using the account we use to pay as our main ones, and secondary ones to increase our total storage limit beyond 1 TB without paying for a very expensive upgrade. Microsot isn't stupid. They are doing this to increase revenue. It will backfire because users that are sophisticated enough to do this (which was procedure THEY used to tell us to follow, by the way, when more than 1 TB per account wasn't available) are also aware they might move on to another service if OneDrive stops working properly.