After re-reading and reading many other comments in various posts I think I have misunderstood it partly.
So the workers part has been overhauled in Rust for Synapse Pro. Is this a complete re-implementation of Synapse so the big deployments with Synapse Pro will not run anything from the normal Synapse or is this only part of the whole stack and the Pro deployments will also run most of the normal Synapse?