I've found one can leverage a little potential evil also known as Google Drive to:
- place a text file therein
- change its access to be accessible to anyone with a link to it
- obtain its link, e.g. https://drive.google.com/file/d/1qbSOCmFVqCOPD_zLIvG-Kb3cp9LEsHIm/view?usp=sharing
- modify that link to leverage accessing it by download, i.e. https://drive.google.com/uc?export=download&id=1qbSOCmFVqCOPD_zLIvG-Kb3cp9LEsHIm
- point "curl" to that thusly: curl -s -L -o- 'https://drive.google.com/uc?export=download&id=1qbSOCmFVqCOPD_zLIvG-Kb3cp9LEsHIm'
That brings the text content to stdout, which could be redirected to a file, which could be diff'd against a copy of the same file thusly acquired to note changes/updates to the file - and then, of course, one replaces one's copy with the latest for subsequent diff'ing.
I suspect one could also point the likes of twtxt (https://twtxt.readthedocs.io/en/stable/) to such.
Of course there are plenty of devilish details accomplishing some of the above that I'm not going to get into because shit looks different in others environments, etc., blah, etc., blah, and those who'd truly want to make it work will find a way.