this is true, though with the assumption of blogging as it is in today's world where it is lonely and only a search engine can find you. if blogging was done inside a supportive community and network it could be less lonely and you could get frequent feedback and interactions.
If I was to make an analogy using your perspective on blogging with facebook or instagram - you post about yourself or post personal photos for a long time. It is futile, for a long long time, nobody sees your content... you post photos for years, and you realize it changes you. You will notice patterns, you will get better at posting photos ...
I am exaggerating to make a point and it is this, you may find yourself needing to perfect your content strategy(blog, photos or facebook-style posts) for years and the main reason it doesn't pay back is there is no network or community anymore. You shouldn't have to be a pro to get noticed.
People tried decentralized networks and that didn't work so well, because one - you need modern blogging software (newsfeed, real time comments, spam moderation, good recommendation algorithms) and it has to be managed by a centralized authority that offers a great user experience. Today, closest thing to this is facebook and twitter (and instagram). All in all you must have these for a great blogging experience: first, good software and central authority, then network. It must be focused on serving authentic bloggers, and it must be backed by a commercial solution.
That in turn means, a paid service, whose customers are bloggers. That means, how badly do you want an amazing blogging experience, where you blog with great writing tools, search, discover, and interact with others (and probably in today's world, be able to hop on a video chat with your viewers and share that in comments). Yes, so how much do you desire to have it, would you pay $5/month? $30/month? $100/month? It comes down to this.
If there was monetary backing, this problem could be solved with a 'solution'. Chances are that not enough many people want it, and people are content with free posting on instagram, twitter, or facebook, and happy to live with ads. If this was a high demand service, chances are that it would have already been built, or existing ones would already be prospering (tumblr didn't make money and got acquired, blogger shut down, medium serving writers looking to make money, recreational blogging is not their target and so on). So is this a real problem to solve or not?
Maybe people don't know they want it and aren't organized enough to support it, - if you built an amazing experience maybe lots of bloggers will pay for it, then it will become another, facebook where the network is funded by its users.