This looks great! I was about to start learning and diving into Obsidian about a month ago, finally driven to begin building a personal knowledgebase...
And then I found Mem.ai and dove into that instead, and i've been extremely happy with it. It accomplishes this aspect he's offering here (where it uses your knowledgebase to assist in your writing). However, it's also got built in chat with your knowledgebase, and helps with auto-sorting and all of that.
For those that want their data on their computer, I totally see why Obsidian is the most desirable. So this sort of addition would be the best of both worlds for them.
I'm not sure a offline-first document editor is comparable to a hosted SaaS about AI. This plugin is one of many, while mem.ai is non-customizable tool where someone else owns your data and seems to offer no data portability.
I haven't used Notion, but in my research its AI feature is only the Smart Write/Edit that Mem has - tho I am unsure how well it uses the rest of the content you have inside of Notion, as their sales page doesn't really make that clear.
Mem.ai has integrated many aspects into it - I love that I am now unconcerned about tags or folders or categories.
And then I found Mem.ai and dove into that instead, and i've been extremely happy with it. It accomplishes this aspect he's offering here (where it uses your knowledgebase to assist in your writing). However, it's also got built in chat with your knowledgebase, and helps with auto-sorting and all of that.
For those that want their data on their computer, I totally see why Obsidian is the most desirable. So this sort of addition would be the best of both worlds for them.