You mention to wipe system but OP instruction states
(NEVER wipe System or Persist!)
This is why I'm always confused of how exactly I should proceed with clean flash
Where are you now? Phone; ROM; version; working; bootloop, etc?
Where are you trying to get to (I understand you want a clean system and going from Android 10 to 11)?
I'm speaking from my own experience (Mi 10 - umi)
To generalise, if you have a working system, and your upgrade from Android 10 to 11 does not miss out many weeks, there's very little that needs to be done.
You should not need to wipe, format, or interfere with the system. You would do your normal update.
(Unless developer instructions say otherwise.)
(If you are going, for instance, from stable to weekly beta, then you would typically need to format the data partition.)
If you want a 'clean' system, then, after your update (which I presume will be working), do a Factory reset.
A Factory reset from within TWRP normally keeps all of your files but resets the system from scratch. If you want a complete wipe and reset, then do the Factory reset from within Settings.