For me, I subscribe to all the multiple ones of the same topic and let time sort out their popularity.

It's not dealt with. You subscribe to one or many of them and then your home feed will show what it shows. People should not be cross posting unless you are actively involved in multiple similar communities and intend to participate in multiple identical discussions.

If you are just posting a link, provide no thoughts of your own and then do the same in multiple other places then your post is close to worthless and is more like an ad.

I think this could be "solved" on client side. On Reddit you could (can? Idk) merge various subs to a single view, maybe clients like Memmy could do the same.

They haven’t. I’ve given up on finding new communities at this point since it’s a ton of work to figure out which ones are active and which ones are worth subscribing to.

It’s one of the biggest problems with the platform, despite it also being one of the biggest selling points.

Not just that, but if I have a question about, say, Linux scripts, then I have to search fifty fucking communities names c/Linux in fifty fucking instances to find a solution.

Just because an instance has the biggest community doesn't mean it will have an answer. So I do have to look at fifty fucking instances.

I haven't seen a single viable argument that justifies this irritating and inconvenient situation except i LiKe fEdErAtIoN.

And for the federation fetishists, yes you can have federation AND one single c/Linux across instances.

If you don't want to read Linux tips from lemmy.naziLinuxUsers.com then just block that instance like you would block a nazi individual on reddit.

This problem is so ridiculously easy, but for some reason the mediocre status quo always has its ardent defenders.

Sign up for as many of those communities as you want. Unsubscribe from the ones you don't like.

Not in any singular way, it is handled however those people wish to handle it. They have freedom.

https://lemmy.world/post/75670?scrollToComments=true

Or any of the other threads coming up in the search: https://lemmy.world/search?q=multiple%20communities&type=Posts&listingType=All&page=1&sort=TopAll

I love how this question gets asked again and again and there really isn't an elegant answer.

This is Lemmy's greatest weakness, in my opinion. It's too decentralized. I want one place (Lemmy) to go to for everything about my topics of interest. Everyone keeps explaining it as "lemmy.world is like Reddit and lemmy.ml is like Twitter." No. No it's not. It's all Lemmy. It's just that there are multiple Lemmys, each with their own separate sections for each topic, and anyone can make a new Lemmy at any time. That's a problem. I don't want to become part of a community, no matter how big and popular it becomes, only to find out that there is a better one on a different Lemmy server and I've been wasting my time this whole time. This just means that if Lemmy were set up properly then that better community would have been the one that I would have found because it is easy to find and the website design lends itself to finding relevant topics of interest. Right now Lemmy is so frustrating to use. It looks worse than Old Reddit and is less user friendly than New Reddit. Lemmy will never see the popularity or usefulness that Reddit has had if it stays decentralized like this. Imagine asking your friend where on Twitter they found an interesting post and they reply, "No, no, it's not on Twitter 35, it's on Twitter 83." That's dumb as hell. We don't need multiple Reddits, multiple Twitters, or multiple Lemmys.

Sign up to all of them, and post to the most popular/the one that feels to be the best.

I dont think you understand the point of Lemmy. Lack of centralization is key! And not just of instances, but communities too. Fragmentation is kind of the point.

I think the happy medium will be front-end functionality that allows users to collate subs into "multireddits" and have easy access to their multis. The act of subscribing to new communities is not that hard, and interacting with them is more or less seamless on a full feed. The only time I find it gets tedious is if I just want a feed of niche content. It may indeed resolve itself over time, but for now it's a bit annoying to track down my subs to 5 different woodworking communities across 4 different instances. The good thing about handling it optionally and on the front-end is that there's no need to rethink ActivityPub at all and the feature would remain useful even if certain communities become the go-to for a given topic.

What topic only has a single site where the community exists? I followed lots of stuff on Reddit but there were always tons of other related sites I frequented, and there still are.