Cache management is a real pain. The best thing I've come up with is "Debug -> Reset App Data" The message is scary, but it is the nuke option Daniel referred to.

But what I think would be helpful is to simply have a maximum size for all cache. Descript would then automatically delete the oldest projects' cache when it gets close to that number. Alternatively, you could specify a max retention, as in how many days to retain the cache of a project. Personally, I would set mine to 8 days, as I almost never go back past last week's podcast episode.

Yes, please, Library/Application Support/Descript is currently taking up 90GB of my 250GB laptop disk space and I believe I've done "Clear local cache" from all my projects (though its hard to know, I have > 100 of them). Not sure how else to clear up disk space.

Descript used to have a column for this but its no longer available on the Projects overview screen as far as I can tell, so you just have to go 1 by 1 and click on the ... overflow menu to see if the "Clear local cache" option is available.