I've built my career on trying to explain this human element to technical people, and if anything, my job security only improves year over year. I see this same attitude in the Linux community: a willingness to work around UX issues because of perceived benefits in other areas. This is why Linux remains such a niche OS for consumers. No user should ever, for any reason ever, have to open a CLI to install a program. But try arguing that on any distro forum and expect a world of hurt.
Your prediction could come to pass only in the case of the open backend being tied to a massively popular service that could compete with those giants
I don't see what's particularly difficult with hosting a static or mostly-static site, and why you'd have to be really good with it (many early content creators weren't). With Apache shared hosting (where your domain, certificates/acme, and basic htaccess are setup for you), this is a matter of putting a couple of HTML and optional CSS files into your document root via ftp/sftp back in the day, or scp, or WebDAV. And HTML is really not that complex a format (or at least used to be before responsive/mobile web), being based on SGML which was designed as structured text format that can be created with a plain text editor in a way that's being taught in secondary school for decades now, and tips available in magazines etc.
In the old times, you could only host content if you were really good with the technology. The people who had websites were people who knew how to set up and run a web server, and to compose the HTML content that was being served. Similarly, communities who ran BBS forums, mailing lists, IRC, etc. all needed at least some people who could set up and manage the technology for them.
Centralized services (Web 2.0) changed that. Now all of a sudden you didn't need to run your server --- you could just type some text and click some buttons to put up a blog on a shared service (myspace? blogger? wordpress.com?). You didn't need to run your own forum or mailing list or chat rooms, you could just put your community on an existing service that provided that (Google groups, FB/Whatsapp/<insert your IM> Chat). Need a forum? You have reddit. What is Twitter if not just a collection of mailing lists that you can openly subscribe to but not post on? Centralization allowed the vast majority of people to do what they wanted to do while "outsourcing" the technology part to somebody else, because most people don't care about the technology they care about their content.
The problem with the modern decentralized web (3.0?) is that we haven't focused on solving the real problem --- making it easy to manipulate _content_. If anything, setting up a Web 3.0 presence is _harder_ than it was on a centralized service, and as long as it remains harder, the new "old" Internet will always be a niche.