The problem is you broke compatibility now.
Will you do it again next year, and fix 100 plugins once more?
I am also not a big fun of extreme forms of compatibility, but plenty of projects try to break it only to have people which stick around with old versions for years.
Big projects like Python only break compatibility once every few years, and a lot of thought goes into it. I think it's a lack of respect to the authors of Python and perhaps a lack of authority of Guido that packages are not being upgraded to Python 3.
I wonder what would happen, if just a few companies that actively use Python, like Google, would hire a few devs that for a year would only fork and fix Python 2 projects. Wouldn't it just solve the problem? I bet they'd be done within a couple of months too, and they wouldn't even have to be super senior types.
Almost all major Python packages have now been upgraded to Python 3. For example, only 3 or 4 of the Top 50 have not been upgraded, and all but 1 of those are in the process of updating.
It's now mostly just the thousands of smaller packages that still are on Python 2 only.
But Python couldn't get away with that more than once every 10 years.
I am also not a big fun of extreme forms of compatibility, but plenty of projects try to break it only to have people which stick around with old versions for years.