People keep talking about going to another platform. Personally I think a better idea would be to develop lemmy to deal with these issues. This must be a fediverse wide problem. So some discussion with other admins and the developers is probably the way to go on many of these things. Moreover you work with https://opencollective.com/, can they help. Beyond this, especially CSAM, there must be large funding agencies where one could get a grant to get some real professional programming put into this problem. Perhaps we could raise funds ourselves to help with this too.
So frankly I would like to see Beehaw solve the issues with lemmy, rather then just move to some other platform that will have its own issues. The exception may be if the Beehaw people think that being a safe space creates too big a target that you have to leave the Threadiverse to be safe. That to me seems like letting the haters win. It is exactly what they want. My vote will always be to solve the threadiverse issues rather then run away.
Just my feeling. There may be more short term practical issues that take precedence and frankly it is all up to you guys where you want to take this project.