Have you looked at the mod_sftp for ProFTPd? It seems like ProFTPd is alive and well, despite its official site not supporting HTTPS! It seems like mod_sftp supports most of the SSH/SFTP-specific features, whereas ProFTPd may also offer additional features that complement the mod_sftp module. All in all, probably not a 100% match, and definitely not a drop-in replacement, but at least a seemingly viable/supported alternative?

Python? This will require “specialized hardware” just due to the interpreter overhead taking continuous screenshots of everything you do and indexing/storing them. Why bother implementing something like this using an interpreted language??