I was noticing that. I've got a good old banjo, but other than that I'd be doing everything the old fashioned way, which a banjo is also now as well. After that video I went down this rabbit hole and there are a whole slew of tools on my list now.Sorry to do that to you. Between having a Banjo (tape / mud box) and that finishing box like I linked in the video the guy was making short work out of the 2800-odd square feet of surface in the shop.
It certainly would cut down on the time spent getting the tape and fill coats on, so looks like they would be money well spent for a large enough job. I'll certainly look into rental of them for sure.