Thanks for pointing that out.
I'm already monitoring the situation in my setup since using the upstream "fix" and did not recognize anything which I would call "significant". So can you specify what you meant with "significant speed disadvantage"?
I don't think so. The patch by selbitschka works very differently than the "fix" that Stoiko Ivanov authored and was commtted in pve-storage.git.
The -w option enables raw sends, which sends the entire dataset as-is, it does not decrypt it, nor...
Looks like the most recent version of PROXMOX 9.2.2 has implemented a permanent fix for this, see this commit:
https://git.proxmox.com/?p=pve-storage.git;a=commit;f=src/PVE/Storage/ZFSPoolPlugin.pm;h=c705a2c03f2c5a9c67695d5d998925875d95c50b...