Caveat: I'm writing C++, not C# but, Rider does out of the box what I used extensions for for the best part of my time working in Rider to start with. The IDE is faster to start up, faster to use, the tooling works better than the visual studio tooling, the licensing is sane, the source control integration is an order of magnitude better than VS's. The code completion for intellij tools is what you'd expect, for VS it's... varied depending on whether or not VS has parsed your project yet (and good luck figuring out when that is).

Code formatting tool support was substantially better (although still not ideal) in rider than VS, and VCS backed project settings mean that we can have developers auto format locally rather than building out tooling to enforce it.

Cross platform support, with remote editing is also a huge one for me. I have a windows workstation and a Mac as a secondary workstation. Before, I had to remote into the mac and use XCode to debug/build issues on the mac, now I use rider with remote support for 95% of my mac needs, and on occasion when I do need to drop back to the mac, I'm using the same tool rather than xcode.

Until 2022 (which granted I haven't used), VS was 32 bit which despite MS's frequent assurances wasn't a problem, was. Running OOM was a regular occurance on large projects for me over the last 10 years.

Roslynator is a collection of refactoring enhancements for VS. Resharper/Rider add a ton of things beyond refactoring. Its unit test runner is way better (IMO) than VS's native test runner. Support for Unity & Unreal Engine development for game developers. Rider works on Linux, Mac and obviously Windows.

I've been a happy R# customer since 2006. Since then I converted to JetBrain's all products subscription - DataGrip is a really nice database management GUI that supports nearly every database you could ever want (from SQL Server to Postgres to MongoDb!) If you do any frontend development Webstorm is IMO a much better experience than VSCode.

Rider has all of ReSharper but without the performance hit that you get in VS + ReSharper.

Ok, but I've been talking about Roslynator (free refactoring extensions), not Resharper

I haven't tried Roslynator (since I stopped using VS years ago), and to be fair you said "extensions like Roslynator". Just trying to give a bit of an elevator pitch for Rider. The analyzers in Roslynator would definitely still work in Rider (that's just a Roslyn compiler feature), but not any extension-only refactorings, that's correct.