Thanks for reaching out here and welcome to the Community. We're happy to shed some light on the situation.
We can see from your shared screenshots that you're on our New Desktop Experience which we're currently testing. You'll now find the local files folder in Your Library, next to the Liked Songs playlist.
You're welcome to leave any feedback you have related to this update in the thread here. Our developers are taking everything that's being shared in there under consideration, so any suggestions you have to improve the new experience will be greatly appreciated.
Hope this info is useful. We'll be here if you need help with anything else.
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