You're definitely not alone in having a problem selling gear :)
So the thing with this is you can do things like roll potential good pieces of gear to 4/8 and see if it rolls well, sell if it doesn't. This was the video I watched which helped me start to realize I was hoarding way too much:
https://www.youtube.com/watch?v=-CXMKVIVanI&ab_channel=MurderIncRaid
There are tons of other videos out there on helping with gear cleansing, and I strongly suggest taking a look at one of them when you get a chance. Your silver will thank you.
Though I think 1300 is more than enough for artifact and accessory storage, BUT as we see more sets being added I would imagine storage has a shot at being addressed, again.