it's definitely in acm's interest to do so if they want to claim they're 'open access', and it's in your interest too
i agree that it's beneficial to have a central, trustworthy source. if redistributing cacm articles is clearly legal, and the acm goes under, you'll get them from the internet archive, wikisource, project gutenberg, google's new historical acm article archive, or some similar institution. if redistributing cacm articles is not clearly legal, you'll have to get them from library genesis, sci-hub, or the pirate bay, with the associated risks of incorrect contents—but only until those get shut down following a change of government
well, maybe you personally won't, because you have a position at a university, and you can easily just use its library. but the people you'd like to have as your students 20 years from now, people who are now living here in argentina or in ukraine or egypt, will have to get them from there
an additional issue is that, in many cases, the 'central trustworthy source' does a really bad job of scanning paper documents: they use bilevel scanning for photographs (sometimes even color photographs), scan at very low resolution, chop off the pages, and so forth. i run into these constantly; https://www.nasa.gov/history/alsj/a17/A17_LunarRover2.html is probably the most recent example. although allowing other people to scan their copies and distribute the scans does not ensure that they will correct this problem, prohibiting them from doing so reduces the chances further
analogous remarks apply to translation
and that's why the berlin declaration enshrines the right for readers to redistribute works and derivative works as central to open access
i agree that it's beneficial to have a central, trustworthy source. if redistributing cacm articles is clearly legal, and the acm goes under, you'll get them from the internet archive, wikisource, project gutenberg, google's new historical acm article archive, or some similar institution. if redistributing cacm articles is not clearly legal, you'll have to get them from library genesis, sci-hub, or the pirate bay, with the associated risks of incorrect contents—but only until those get shut down following a change of government
well, maybe you personally won't, because you have a position at a university, and you can easily just use its library. but the people you'd like to have as your students 20 years from now, people who are now living here in argentina or in ukraine or egypt, will have to get them from there
an additional issue is that, in many cases, the 'central trustworthy source' does a really bad job of scanning paper documents: they use bilevel scanning for photographs (sometimes even color photographs), scan at very low resolution, chop off the pages, and so forth. i run into these constantly; https://www.nasa.gov/history/alsj/a17/A17_LunarRover2.html is probably the most recent example. although allowing other people to scan their copies and distribute the scans does not ensure that they will correct this problem, prohibiting them from doing so reduces the chances further
analogous remarks apply to translation
and that's why the berlin declaration enshrines the right for readers to redistribute works and derivative works as central to open access