I never posted on Reddit, I only commented, because every time I posted anything, someone would come be an asshole about it. Here tho, I've been posting a lot more than I ever did and I don't get abused for it, unless that was my intent.
The only thing stopping a viable replacement for YouTube is the servers, google essentially has an infinite amount of server space, you would have to match them on that, decentralization would help bare the load, but there will become a time when even those servers will need to dramatically expand their server count.
Only slightly bigger than Australia and Western Australia is nearly twice the size of Texas..