actively archiving is the only way, companies can't be expected to and won't host things that are not in the business current plan, even if sometimes they get it wrong.
i am more surprised by how many old drivers are still available from official outlets, i think they are sometimes just left in place and may eventually disappear through changes in website layout, operation, broken links, retirement of old servers and so on.
its a race between digital copies of old drivers lasting long enough online and actual hardware lasting long enough to use the driver 😀