Maybe some relays are slow/laggy ? Once I switched to paid relays only I noticed a big improvement
Discussion
How do I switch to paid relays?
https://nostr.watch/relays/find
You can filter by paid relays and also by latency.
Once you find one you like, before adding it to Damus, paste the address into a web browser. It will bring you to a page where you can pay in sats for your access