[tbodt]

Aside from being illegal, defeating the various layers of obfuscation and extracting the private keys requires a very particular set of skills, beyond the reach of most programmers. And then they'll just rotate the key and add more obfuscation, once they're done suing you out of existence.

[sneak]

Reverse engineering publicly available proprietary software distributed as freeware to reimplement free software replacements is not illegal.

[tbodt]

Can you help convince me of this?

Also I'd encourage you to contact the owners of the repositories listed in Google's DMCA notice against the Widevine cryptographic key and help them file a counter-notice. https://github.com/github/dmca/blob/master/2020/11/2020-11-0...