I don't blame him. I made the same design choice for my python library[1]. I also don't use any non-native libraries in the single file. I'm sorry to say it's a much better experience for users if they don't have to deal with pip if they don't want to. I myself have been burned many times trying to install some python module for hours and failing because of some dependency issue.

[1] https://github.com/RPGillespie6/fastcov