There’s a big problem with Notion: it still lacks an API. Everything that can be created in Notion must be created either through the app or the official webpage, and accessed either through the app or the webpage. Full stop. No IFTTT integrations, no integration with the filesystem á là Dropbox, no way to trigger changes when something happens on another service, no support for external viewers, no way to sync it with your existing Google Calendar, Trello, Todoist etc. As of now, if you want to embrace Notion then you’ll have to ditch all the other productivity tools you use because it won’t integrate with any of them, and you can only interact with it in two ways — official website or app. A productivity tool with no integrations is like a knife without a blade: no matter how sophisticated the knife claims to be, it’ll always be useless.
Notion is unapologetically late in releasing an API. When they do, I’ll also migrate away from Evernote and Trello and use it as my primary productivity tool, because it indeed solves a lot of problems that services like Evernote have either failed or never bothered to solve. Until then, it’s just a shiny toy that can only live in its own bubble, and it’s not worth for a power user to spend more time on it.