I'm not sure they have technical glitches in the same way lemmy does. Interestingly, the difficulties people have, I think, are because federated social media is actually a bad non-idea technology to use for a twitter clone.

So much either doesn't work how you'd expect or involves new problems that all together they start to defeat the point for many. For example, replies to a post. The author of the post sees all of the replies. But replies aren't actually federated unless certain conditions are met based on whether someone on your instance follows the person writing the reply. As a result the author of a post that receives many replies has to manage/tolerate a bunch of replies that have no awareness of the fact that they're just repeating what has already been said, sometimes many times over. For people replying to a post from a small/niche instance, they basically don't see any of the other replies, which just makes for bad content for them, but also means they constantly risking being really annoying people which in turn effectively punishes small instances. This is generally referred to as "context collapse", and yea, it's something kinda extraordinary when the core feature of a social media platform actively destroys the context of conversations.

Lemmy doesn't have this problem because its based on groups where the whole premise is that the whole conversation gets federated, and for that reason I think a reddit clone or a forum or a youtube-clone (or anything based on groups, sub-reddits or channels) is a better fit on the fediverse.

The other friction mastodon has is that, as a twitter-clone or microblogging platform, its core mechanic is following people and allowing people to form their own network of connections and friendships. But once you've got federation and instances in the mix, where defederation happens, then you have this often completely separate dynamic (ie the relations between instances) capable of completely slicing your personal social network in many destructive ways. Often this happens without people hearing about it (as there aren't mechanics for notifying people of defederations AFAIU), so that they have to find out after some time to realise that they hadn't heard anything from a whole bunch of friends and were wondering what had happened. Moreover, what such people can then do to re-connect with those friends is rather non-trivial. It's probably the major draw back of fedi-drama, that the majority of people affected by it don't benefit from it and would prefer to just be on the big instance (mastodon.social) that no one really defederates from or just go back to twitter.

EDIT (more ranting):

The way someone I like (as a person on social media) put it, after giving mastodon a good shot, was that mastodon misunderstands what people want from social media, that mastodon puts independence over socialising when people prioritise it the other way around ... the whole point is to connect and converse, not to run your own instance and make sure you've defederated from everyone who has it coming.

Now there's the whole issue of making sure someone vulnerable to abuse is able to ensure their own safety and happiness from would-be assholes and abusers and even those eager to voice unwelcome, abrasive and triggering points of view which are generally tolerable because they're the mainstream. Federation across instances can help with this ... but can also make it worse because anyone can talk to you from any instance over which you have no control or information until it's too late. In many ways, decentralisation isn't great for these problems and creates new problems that a centralised form of social media simply doesn't have (not least of which being that the whole thing is about copying you and your posts out to everything on the network). It's for this reason that BIPOC left mastodon and went back to twitter, because to them, mastodon was the racist/facist place, not twitter. In light of that phenomenon, it's worth considering the perspective that decentralised social media might be a bit of a weird idea and rightly seen as a bit of a fanatical and even a bit of a right-wing or libertarian movement.

In the case of group-based platforms like lemmy and forums however, I think it makes much more sense. Many independent forums are out there, and have been and hopefully will be for a long time. Why not contribute Open Source software for such things (such as lemmy) and enable them to connect to each other however they wish.

I've been on Mastodon for over a year and I never experienced anything that could be classified as a technical glitch. From a tech / UI perspective it feels very polished to me.

I guess the only exception would be that old posts are sometimes missing on profiles from different servers.