I've always thought the Evernote sync issues got much less attention than they deserved. Both myself and my co-founder were repeatedly burned by Evernote sync when working on notes between mobile and desktop. Sync was the foremost reason we began working on a replacement.

We picked "sync" and "security" as the two core values we wanted to put most focus on when building our note app (https://www.amplenote.com/).

It's curious to me that Notion has so little to say about the effort they put into sync and security -- these seem like such essential features to a great todo app, and I don't think either can be done right unless it is an active, top-tier priority.