Yeah they originally had a separate branch "Rider Unreal" but now it's part of Rider, C++ support seems mostly the same across both, except for project support. If IIRC Rider doesn't support CMake projects, but it does support vsproj projects, so if you generate vs files from cmake it'll load fine, but probably better to use CLion for any non-UE projects if using C++. I guess they're seeing it as .NET/GameDev IDE.
Honestly I don't know why there are so many almost identical IDEs.
JetBrains IDEs are all the same program just bundled with different language plugins. It would be like if you called VSCode by a different code name depending on which combination of extensions you had installed.
Not entirely. E.g. IntelliJ has a "project environment" modal (not sure about the exact name rn), in pycharm its part of the settings and a bit different. There are a few more things like this between the IDEs.
To +1 this: yes, they clearly share a lot of code, and have mostly-identical plug-in interfaces, and many dedicated IDEs have plugins for the more-general Intellij IDE.
And they present them as "just" a dedicated UI around the plugins.
But no, they are not actually the same. Essentially ever. The dedicated IDEs often have features that never make it into their plugins, and a lot of the UX and project structure/preferences/etc are quite specialized and don't always have equivalents outside it. You get like 90-95% with the plug-in, but not 100%, and sometimes that's a critical difference.
The plugins do have the distinct benefit of allowing you to use multiple in a single project, though.
If you open, say Android Studio (or IntelliJ) and start a new project, then open Rider and start a new project - the UI is actually very different for how the projects are managed. PyCharm is different too in different ways.
I think the differences are more akin to the old Visual C# Express and Visual Basic Express IDEs vs Visual Studio. Visual Studio was always "everything", but you used to get the express versions that were "low cost" or free. They only had the single language in them. They were customised to just that language. This is what Rider is to IntelliJ Professional, except from what I understand, the plug-ins for IntelliJ are not always on a 1:1 feature parity. This can even be seen with Android Studio and IntelliJ Community. The Android tooling in IntelliJ Community is almost the same, but it does miss out some stuff in Android Studio. Because Android Studio is specifically for Android development, and IntelliJ Community is more general purpose Kotlin and Java development. I think the Kotlin Native support is slightly better in IntelliJ Community.
I use both Rider (for mixed c++/c#) projects and CLion for C++ only.
I feel that Rider is somehow better than CLion at c++, even after CLion Nova (Intellisense based on Resharper backend) became a thing.
One difference is that I write boost::asio in CLion, and just vanilla C++ in Rider, and before Nova it was completely unusable with async code, now it's usable with async code, but after a few days of running the editor I end up with fatal IDE errors for CLion, and never for Rider.
