If you are a student or a hardcore Kubrick fan, the Internet Archive is still useful for 2001 —just not for the movie itself. You can find:
Finding the is more than just getting a free movie. It is an act of digital archaeology—accessing a masterwork outside the commercial streaming ecosystem, in the raw, unpolished form that community archivists have fought to preserve. As of this writing, the most reliable method is searching archive.org for “2001 A Space Odyssey 1968 full movie Stanley Kubrick” and looking for the upload with the highest number of “favorites.” 2001 a space odyssey full work movie internet archive link
Rather than chasing a potentially broken or low-quality Internet Archive link, here is where you can access the remastered, glorious 4K version of 2001: A Space Odyssey legally: If you are a student or a hardcore
: An alien artifact that appears at key stages of human advancement, first teaching tools (weapons) to apes and later signaling from the moon toward Jupiter. As of this writing, the most reliable method