Windows NT was not a rewrite of Windows 95. In fact it was released in 1993, well before Windows 95 got released.
It is unfair to say that Python 3 has adoption problems. In fact the rate of adoption is slightly ahead of what was initially expected.
There are a lot more successful rewrites you can add to the list. For instance Perl 5 is a rewrite of Perl 4, vim is a rewrite of vi, and less is a rewrite of more.