the problem is when the safe-harbour entity doesn't actually try to protect their content creators, but blindly accepts any takedown. Youtube is notoriously obedient - to the point where it can threaten content creator's livelihood (see https://www.youtube.com/watch?v=QfgoDDh4kE0 for a famous one).
Doesn't matter - they have to accept the requests and sort it out later to retain safe harbor. That's just the way the law was set up. The whole point is that they claim neutrality - they are the carrier of the information, not screeners or judges of it. The legal back and forth is between the the entity posting the content and the entity submitting the DMCA takedown. After the fact, YouTube to Github can and should and sometimes do help fight back against abuse.
Is there any incentive or law that causes Github to have a DMCA web form?
If it's possible, then it would be a good act of protest to require individually signed (by an actual person with a pen, not a picture of a signature), individually snail-mailed requests. This would at least make the process take O(n) time and O(n) money, making it a bit harder to abuse.
Yes, by following DMCA procedures Github stops being liable for its users copyright infringement actions (safe harbor). Should Github not follow procedures defined in DMCA, Github would be on a hook.
I'm describing a form of malicious compliance. Is there a legal requirement that the request be a web form? Or is it allowed to provide only a mailing address?
If you think this is about copyright in a domain name you're missing the point. The DMCA is being used because uBlock is blocking a technology [script download] that is used to prevent access. uBlock is working like a DRM remover (the argument goes) and so is committing contributory copyright infringement.
Modifying uBlock mitigates the argument but doesn't entirely remove it. For example if the people who control uBlock control a third-party source that allows the same preventions to be implemented then technological changes have been made but the situation is legally homologous (AIUI, IANAL).
IMO uBlock need to provide facility for a domain to be blocked but say "search online to find blocklists" and have no legal associations with the blocklist maintainers; akin to how emulator sites manage ROMs, they stay as legal separated from them as possible. Putting Google in the middle makes getting sued harder, in theory Google is linking the people to the tech/info that enables the alleged infringement.
Remember DMCA is strongly weighted towards the accuser in the initial instance and that a service provider has to take down content in order to maintain their safe-harbour protections, leaving it to the alleged infringer to counter the accusation (guilt until claim of innocence).
The lmgtfy was meant towards github's lawyers, not you. My point was that this is so obviously invalid that they should absolutely have flexibility to challenge it.