I spent some time looking for a post like this and it didn't exist on the Google machine, so here we are.
My Hisense android tv kept interrupting me mid-show saying it was running out of space. I had deleted the unused apps, but x-plore helped flush out another 2gigs. Here's what you do:
*Download "x-plore" on your android tv
*Use the "disk map" feature in the middle pane to see where large files are hiding. For me, I had a 1.5 gigs in "trash", and another gig in folders that didn't seem important
*Navigate to said folders and delete in x-plore
When looking at the "internal shared storage" in my android tv settings, I couldn't figure out how to delete the "Misc." Category. The above process was the answer.
Hopefully this helps someone else searching around.
X-plore is one of the most underrated apps on android. I've used it since Symbian days. I've tried all the others but dark mode X-plore is what I kept coming back to.
Simple and efficient, moving things across LAN, cloud storage, wifo server etc.