I don't see how Lemmy will fill the gap of Reddit - it's resulting in fragmentation

Perhaps I've misunderstood how Lemmy works, but from what I can tell Lemmy is resulting in fragmentation between communities. If I've got this wrong, or browsing Lemmy wrong, please correct me!

I'll try and explain this with an example comparison to Reddit.

As a reddit user I can go to /r/technology and see all posts from any user to the technology subreddit. I can interact with any posts and communicate with anyone on that subreddit.

In Lemmy, I understand that I can browse posts from other instances from Beehaw, for example I could check out /c/technology@slrpnk.net, /c/tech@lemmy.fmhy.ml, or many of the other technology communities from other instances, but I can't just open up /c/technology in Beehaw and have a single view across the technology community. There could be posts I'm interested in on the technology@slrpnk instance but I wouldn't know about it unless I specifically look at it, which adds up to a horrible experience of trying to see the latest tech news and conversation.

This adds up to a huge fragmentation across what was previously a single community.

Have I got this completely wrong?

Do you think this will change over time where one community on a specific instance will gain the market share and all others will evaporate away? And if it does, doesn't that just place us back in the reddit situation?

EDIT: commented a reply here: https://beehaw.org/comment/288898. Thanks for the discussion helping me understand what this is (and isnt!)