There’s no reason to believe they won’t have an online copy of the 2020 snapshot too. Isn’t that kind of the point? For future generations to be able to use it?
The online copy is... GitHub itself. Which is current and up-to-date, and you can continue to remove your data from. The 2020 snapshot is useful historically... like a time capsule. There's no reason to invest the resources in keeping it online. And if it was online, it would have major regulatory problems, such as GDPR.
So there's a lot of reason to believe the 2020 snapshot won't also be online.
It will likely apply, still I imagine that they can simply pretend it does not.
My intuition is that archiving data for long term historical use is different from datamining a [meta]data to maximize invasion of privacy. Also there is a difference in accessibility, stored inside a glacier very few people are going to actually read it.
I believe that if mass complaints from all over the EU emerged it would be a different story. But this does not look like the activities the GDPR was created for
This makes me wonder: How does GDPR apply to books? Essentially what's happening here, is that GitHub is printing off a "paper copy" and putting it in a box somewhere.
You can't exactly GDPR request deletion of your information from a printed book, so I'm curious how GDPR applies to such physical archival mediums.
So there's a lot of reason to believe the 2020 snapshot won't also be online.