First impression of mem.ai
If you have not used mem.ai, you should.
Great note taking tool, does several things well as this article highlights.
It's a one-way street, you can only input information, you cannot take out information from them. If you write an article on mem.ai (the authoring interface is super-nice), but you cannot export the article (copy and past, meh!). There is no support for tables either or no integrated database like Notion.so supports.
A long way to go, but looks promising. I am using it anyway and will continue to use as long as I can.