YSK: If you want faster and less buggy User experience, move to a smaller instance that is hosted close to you.
I have been using Lemmy for 20 days, at first I opened an account at Lemmy.world because you can join without writing a text and waiting approval. I have been enjoying the experience overall but despite the admin teans best efforts Lemmy.world has been experiencing some serious performance issues. If you want to avoid that join a smaller instance, preferably hosted in your country. I joined discuss.tchncs.de today and everything is so much faster it has added benefit of being able to see beehaw.org posts too. It will improve not only your but all other Lemmy.world users experience too.
Agreed that close helps in general but 200-300ms isn't really that noticeable unless it's something where latency is important. I'm also surprised that some of the larger instances aren't using Cloudflare for caching. If things like images etc... are cached all over the world then I doubt anyone would notice any speed issues.
Yeah being overloaded is definitely the biggest factor but servers being close also helps especially when you have a slow Internet connection. That is why I added bring close part as "preferably"