Yeah, it's read-only.
IMO that's still better than other sites, where they don't federate at all.
On Reddit, you can screencap something, and paste a static image. You can't see the comments underneath at all.
I expect instances that don't fully federate will grow slower, so it won't matter, most content will be on instances that are open to fully connecting with others.
Made myself a fused beehive staff in TOTK and feel like a beegod.