It would be interesting to know how many modules were removed since Rack V2 was published.
For plugins/modules that haven’t been ported so far, I keep an inatllation of Rack V1.1.6 on my system.
One thing this thread and a similar thread here Can a patch embed modules ? tells me, not to remove modules from my plugin because I think they are obsolete. Best practice should be to never remove a module.