Desktop design decisions. A lot of folks hated Unity. I know I did - they turned something familiar into something Apple like and I couldn't stand it. I'm genuinely not a fan of the unified menus and such. It didn't help that users were basically forced out of Gnome 2 into it when Unity became the default.

Within Unity they Integrated Amazon results into the Desktop Search. That was likened to spyware since your queries were being shared with Amazon, much like MS integrating web results into their own search. Ubuntu fucked up harder because, absent any filtering, their search occasionally produced adult products in the results - ie sex toys and such. Imagine telling your kid Fluffy needs a new knotted rope chew toy. They start searching "dog knot toy" just to have the results filled with BadDragon knockoffs.

They've leaned heavier into enterprise over the years and that has alienated a lot of the Desktop audience which helped bring attention to OS in the first place. They went from "Linux for Human Beings," making desktop computing more accessible throughout the world, to becoming essentially the Microsoft of the Linux world.

Their snap backend is proprietary. You can't just host your own snap repository. Even if you host your own local snap cache, it ultimately must point to and retrieve from their repository to populate that cache.

I'm sure there's other stuff worth pointing out that I've forgotten.

GNOME (by default), Snaps forced on you OOB rather than being an optional thing during setup or in any of the GUI settings, locking newer security updates behind a subscription, and Cannonical just being a bad captain of the ship.

There's a reason why Mint is hailed as the new "casual (non-gaming) user favorite", since it's literally just Ubuntu sans GNOME and the hostile update design decisions.

Too much corporate control and enshittification. For example, when you use apt-get to get native packages, it can instead download a snap package (which works differently, is controlled by them and might not be preferred for many other reasons), even though you clearly meant not to.

Canonical (Ubuntu's developer) is trying to push people deeper into the ecosystem they build and control.

Then, they roll out a paid Ubuntu version, Ubuntu Pro, separating paying and non-paying customers and turning Ubuntu into a subscription-based SaaS.

I don't hate it, it's just so far the worst one i've used. It's not necessarily bad, I have friends who use it.

Widely and loudly hated, but not universal. The fans just aren't that loud ;)

Because apt is fundamentally broken and it shows most readily on a desktop-oriented distro like Ubuntu.

In order to benefit from packages not included by the distro you need to use 3rd party apt repos, but there's no rule against those repos using package names used by another repo, including the distro's repos. It could've also been fixed by identifying packages by [repo name + package name] instead of just [package name]... but it hasn't.

The result is that when Ubuntu packages get replaced by 3rd party packages by the same name it can mess up the dependency graph if the 3rd party repo isn't super careful about it.

It's not a huge issue immediately after installing something but as time passes and more updates pile on top of each other (from both Ubuntu and the 3rd parties) it can get completely ruined and eventually the update solver can't find an upgrade path anymore and you can't use Ubuntu's newer releases.

At that point you have two options. One is to use an advanced solver like the one in aptitude, for example, but in order to fix the mess it will recommend to uninstall and reinstall a huge number of packages, including very core, essential packages, which is very risky and you lose the 3rd party stuff anyway. At which point you might as well use option two, which is to reinstall a newer Ubuntu release from scratch.

Eventually after you go through this a few times it starts to get really annoying and you either get stuck on an old release out of dread, or you start looking for a distro that can be updated in-place indefinitely.

Hate is perhaps too strong of a word, but personally, I just don't care for their default desktop environment. If I had to, I could still use it but as I have lots of choices I'm going with something else.

On the other hand, I find Ubuntu to be a fine server OS, especially if you want something in the Debian family but want something a bit more up to date than what's currently in Debian stable but still widely supported.