Rider 2021.3 has an M1 build, and makes a big difference. It's currently in preview (https://www.jetbrains.com/rider/nextversion/) but will be released in the next week or so.
I wonder if JetBrains has some incentive to keep Mac users happy at the expense of others, because there is no justification for the unacceptably bad performance of CLion, PyCharm, and IDEA with a version 11 JDK on Linux, given how much better it is on JDK 15/16.
I have never seen any indication that they have are going to address this, nor have they even acknowledged that it's a problem, nor that they intend to upgrade from JDK 11 to something more up-to-date. Still, they have 1 year and 10 months from now until the end of active support, so perhaps this might provoke them into action.
The fact that JBR even exists is a red flag. Should every vendor ship their own JVM?!
https://youtrack.jetbrains.com/issue/JBR-3729
tells that JetBrains have been working on a JDK17 version of JBR for 2022.1, which amazingly, is almost upon us. I am looking forward to seeing what it's like!
Instructions are here: https://iam.georgecox.com/2021/11/24/making-jetbrains-ides-r...
(I am very keen to tell people who are in the same despair as I was about how slow JetBrains apps are out of the box -- hope it's not considered bad form to link to one's own blog post about it.)