I really couldn't care less what anyone else chooses to use, that's their choice, be that the web browser or the OS.
I like Win 10 and Edge, and that's what matters to me, as it's me that is using it. At the end of the day, which OS and which browser is best is only a matter of personal opinion.
As for take up figures for Win 10 vs Win 7. I take a pragmatic approach, and in my opinion you have three and perhaps more distinct type of users.
1, Those that have tried Win 10 over an extended period and love it.
2, Those who have tried Win 10 over an extended period and hate it, and have gone back to Win 7.
3, Those who have tried Win 10, and simply because its different to use than Win 7, and doesn't seem familiar go back to Win 7. And then they bitch about how Win 10 is the devil in disguise.
To each their own, stick with what you like.