Maybe a myth for you, what do I know, I have only been using and tinkering with Android since 2009.
Everytime I swapped a rom or had to root/ upgrade a device to a newer version of Android, I always followed it by wiping the cache partition, never faced any issues.
There was a time when I didn't know about this, used to face bootloops and bricking a lot.
So, I'll stick with my myth for the time being now.
I know that after wiping the cache the phone has to rebuild it from scratch, which would take more juice out of your CPU, but having been through the horrors of bootloop, I'd take a myth over that nightmare any given day.
These new changes (discarding caches prior to boot) came into effect after Android 7, if I'm not wrong.
I know that in theory, it might not have an effect, but having done this for a long time, this just gives me a better assurance.
Last edited: Sep 26, 2021