If you will allow me to respectfully disagree, the mere fact that you can make this post at all is evidence against what you are saying, no?
e.g. Reddit has “posts”, which may have links to “YouTube” or “Wikipedia”, or to “Tiktok” or “Instagram”, or “Facebook” or “LinkedIn”, etc. - each of those requires a different account (the former three at least allow anonymous viewing, the middle two make it extremely difficult but it can be done if someone has a link to a specific item of content, while iirc the latter two mandate having an account to view the content at all).
Within each component of the Fediverse, it seems connected to a very high degree? e.g. the one we are discussing this on here now is the Threadiverse, which can be read, interacted with (voted, saved, links sent to) and commented on by people with accounts on any instance running Lemmy, Mbin, or Piefed (among Threadiverse software platforms I have also heard of nodeBB and flarum but I do not know what the current status is of their ActivityPub protocol integration). This level of interactivity is high.
And beyond that, you can interact with it via Mastodon, Misskey, Friendica, etc. Granted, this level of interactivity is much lower… but at least it exists? So it is high compared to not being able to interact with it, if that makes sense? A better phrasing might be that something is better than nothing?
And with effort put in by people donating their time & energies & attention & skills, it will improve. e.g. I am writing this to you from PieFed where new features are added practically every week (in fact it is nowhere close to being uncommon to see changes every other day). So what you are asking - it is happening, right in front of our very eyes! It might just seem slow to someone more used to “capitalistic” rather than socialist endeavors because it is not backed by corporate money that would seek a return on their initial investment, e.g. by selling user data, and instead requires the donations (especially of effort and skill, but money works too!) of individual people.
Diagnosing an issue, on a matter that you feel passionate about, is a first step towards finding a solution for it. So now that you are walking partway down this pathway, I hope that you continue - donate or help directly if that sounds fun to you! :)
And welcome to the Fediverse:).