HelixNotes is completely free, open source, with no bloat. Your notes should be yours.
So we made sure they are. https://helixnotes.com/
I'm doing this about an intermediate step. My notes are all in a GIT repository. So I use GIT to create the synchronization between the different devices. On the smartphone with PuppyGit. Positive side effect: The note app itself does not require synchronization.