AFAIK it’s a bad idea to use dd or another wiping tool that just overwrites the logical partitions on flash based media, and is also not that effective for security. SSDs have wear leveling and what the computer sees does not map 1 to 1 to what’s actually on the flash chips. They also have extra overprovisioned space inaccessible to your computer specifically for shuffling data around when wear leveling. So not only are you wasting write cycles, it’s not guaranteed to actually overwrite all your data on the flash chips themselves.

If you want to wipe an SSD, use secure erase from a tool like nvme-cli which will directly tell the controller to erase all the data. How well the controller implements that is anyone’s guess though.

I’d say if you’re going to the effort of fully encrypting your new install, doing a secure erase will be in that spirit and won’t hurt. There won’t be any performance benefit but it will (probably) ensure that none of your previous unencrypted data is still there, though even if you don’t do this, just writing to the drive in normal use will eventually fill up the free space and make it less and less likely that sensitive information is recoverable, but how long this happens depends on how you use the computer.