Thanks for telling me this. I will definitely avoid Notion now. I want a username/password combo at the very least, both different for every site I use, and preferably with TOTP as well. I never want my email to be used for security purposes as it is among the most hackable target out there.
Yeah dude someone might go through the trouble of hacking your email just so they can find your todo page with an unchecked checkbox for feeding your goldfish.
You have no idea what they want to put in their Notion account. And so what if they want to have high security for something you deem trivial? You gain nothing by being an asshole about it.