The vitriol and insinuations (and mock politeness) are most visible on the board-discuss list https://community.documentfoundation.org/c/board-discuss/, but occasionally also show up uncensored on other lists, like here https://community.documentfoundation.org/t/well-known-high-contributors-were-removed/

One can only imagine what the various non-public mailing lists and online discussions look like.