Is that dump going to be maintained under the new regime? While they can't redact existing data bumps due to the license those are covered by, they don't have to keep publishing updates. If that happens then scraping becomes required for the copy-spam sites and such.
Though that is a bit conspiracy-theory-y and I expect blocking Tor is more an issue of a small but very active number of people using it to create accounts to post anonymous spam or abuse. For that, which can be a very real problem, I would suggest a more fine-grained block: stop people from those addresses creating accounts, or posting from relatively new (or recently inactive) accounts, or perhaps somewhere in the middle: prevent connection from Tor addresses posting at all, but still let people use the site. That way you still block the abuse, but have less impact on others accessing via Tor.
Though that is a bit conspiracy-theory-y and I expect blocking Tor is more an issue of a small but very active number of people using it to create accounts to post anonymous spam or abuse. For that, which can be a very real problem, I would suggest a more fine-grained block: stop people from those addresses creating accounts, or posting from relatively new (or recently inactive) accounts, or perhaps somewhere in the middle: prevent connection from Tor addresses posting at all, but still let people use the site. That way you still block the abuse, but have less impact on others accessing via Tor.