Hi,
we just enabled email ratelimiting in our MTA server [0] in Toolforge.
Please, report any problem or issue you may find related to this.
The current limit is 100 messages per hour per sender address. We may tune the
value as we observe the behavior of the system and the users.
regards.
[0]
https://en.wikipedia.org/wiki/Message_transfer_agent
--
Arturo Borrero Gonzalez
SRE / Wikimedia Cloud Services
Wikimedia Foundation