The culprit is the JDK11-based JBR. I was ready to dump JetBrains tools due to their lagginess, but with some deviousness (which might not suit you), I now have them running slipperier than a wet fish, by using JDK15/16 and JAOTC.
(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.)
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.)