This is good advice. I'm a novelist, and I'm just starting to build a YT channel, mainly turning my Medium articles into videos. I'd also like to add audiobooks of my fiction on there. Many indy authors I've read on here shared that once they realized traditional publishing can't do much to promote their stuff, it's up to them to do it. So I'm building my own platform.
For me, it's Medium and my personal website as the base, my books, then YouTube, then Twitter as a link builder and somewhat distributor. I've yet to figure out the Twitter code, as I hardly have any following on there. But Medium has been great for me as an organic traffic builder.