While researching #419 Found that dynamic trees will cause massive performance hits with flying blocks. My guess is flying blocks are picking up near infinite entries from the tree. Shortly before the screenshot I noticed a massive collider. Its likely dynamic trees is attempt to place a fallen tree but is failing.

Recommend short term solution is to add a black list of blocks and mods. With two long term paths to add after. First having a replacement table of blockState to different blockState. This will allow modpacks to change what is picked up. Second path is to add support directly for dynamic tress to pickup the entire tree or part of the tree.