The biggest issue is that to challenge them, you have to dox yourself, even if the DMCA claim is completely bogus and itself is contains bullshit information about nobody who actually exists (e.g, in a doxing war, the party that fires a bullshit DMCA claim first has a huge advantage).

You pay lawyer, they back off, you're now in the red for lawyer fees. I guess you could sue for damages but good fucking luck