It seems to me like the remaining option that can make everyone "happy" is the previously-suggested option of maintaining a legacy branch and doing new development (reinstating 4.042) in another branch which will be released as a new distribution, like DBD::mysql2, by the same maintainers. (I would not favor DBD::MariaDB as a name, since this new distribution would also be the favored way to connect to MySQL.) After doing so DBD::mysql can be deprecated, with migration instructions added to the docs, and only receive critical security fixes if anything. If done this way the community should not be fractured; the current module will simply be abandoned for future development, all support and maintenance will move to the new one. Patrick and Michiel, what do you think?
-Dan