Does it? It has been over 20 years. Should a creator be able to profit indefinitely off a single work? 20 years is long enough for a patent to expire. The fact that copyright outlasts patents is really just a corruption bug in our legal system.
Patent does not apply here, copyright does. And the US copyright lasts 70 years after the death of the author, and for companies, 120 years after creation or 95 years after publication, whichever is shorter.
Yes it does. The creators also maintained that code, and the other intellectual property, by expabding on it with source and csgo. While I am nobody to poopoo piracy, this is a piss poor justification.