Ok basically json-rpc and company taking >50% of compute . What is the Lsp server you are running? What version of emcas?

Try ‘cd =’, you will get list of previously visited directories with numbers assigned to it. Then do 'cd ’ to jump to the directory.

One thing I do after any major OS upgrade is, I update XCode, command line utils and rebuild emacs. Usually that fixes problems 99%. Of course it takes 1-2 hours to complete this process but I multitask during this time.