You are not alone. I have attempted to get Remote Files to work on and off since April 2023. Using Google as a test, keep getting “Specified Device is Not Valid” error. I was able to get Remote Files to work a few years back, albeit very slow and non-intuitive.
I have recently decided to get back onto this topic. I utilize Ubuntu (version 22 presently) with the 7.3 version of LibreOffice.
Without any interaction with the developers as of yet, I can imagine this is a case of one-step forward and two-steps back. Third-party storage sites have soared in use in the past ten years, with attending security issues. The remote storage applications I have used at the enterprise level usually involve an elaborate exchange of keys for the user, the device and the session. My guess is that this evolving standard has been a challenge for the open source community to keep up with.