I can't upgrade IntelliJ any more, because it's trying to write to privileged file locations that I (the owner of the computer) no longer have access to. Believe me, I've tried to work around this, macOS has it locked down completely.
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A few months ago I installed Rider (an IntelliJ-based IDE) on my Mac without toolbox, and upgrading it was a pain. I don't remember the details, but using JetBrains toolbox makes upgrading as simple as clicking a button and waiting until the download / install is complete.