How to get rid of the "other", kind of content in your iPhone storage?

I had 21GB of apps, music, etc on my 64GB iPhone XR, but I also had 30GB or so "other" unknown garbage and there was no way according to apple support to get rid of it. The "other" garbage accumulated after I started making short 2 to 5 minutes videos, transferring them to iTunes on my iMac and deleting them off my iPhone. Instead of getting more space after deleting, I was getting more garbage.

Called Apple support, who just said, backup your phone and restore it, there are no other solutions. Took me a total of 4 hours to restore my iPhone XR and my Apple watch, get all my credit cards back and re-logging in all my apps and web sites.. was **** !!!

There is a simple solution to that, and I don't why Apple support does not know about it..or doesn't tell its customers... its mind blowing!

So here's what you do, its kind of a complicated, yet simple procedure with many (more than 1) steps, so you might want to read back the many steps a couple 'o times to make sure you remember, you could also take notes:

1 - Power off your phone (iPhone XR hold right button & volume down, use slider to power off)

2 - Turn it back on

No more "other" junk!

When I called Apple support, why didn't just they tell me to do that?!

Will this solution finally reach support... I will call them in a month to see if it made it all the way back to them :)