The purchase of Tumblr was basically Elon purchasing Twitter without the political gain. I'm amazed the purchase decision was ever made, and more amazed that it still exists after the hit to the user base.
That is sad but not surprising. I think they always had a bit more trouble with its sync system than they would have wanted.
I loved Simplenote for the longest time but ultimately simple pragmatism switched me to Apple Notes after dalliances with several task management apps.