"I won't pass your email to third parties. I will send you a newsletter but only if you opt in during account setup. You can delete your data at any time."
As long as there was a tiny link (privacy policy for lawyers) with it written the traditional way. I want to know that a company is able to produce a traditional privacy document, but is also smart enough to know I don't want to read one.
Just kidding, I should come out my own version.
On the other hand, I still have no idea what their product does uniquely outside of any todo list. Thus, there is no value for me there outside of the proposal of "Deep Work" which I remember fondly due to the book.
In simple terms, signing in with my account extracts an imagined cost (A company(?) has access to me), and the value presented is not enough for me to justify that cost.
Adding other screenshots, and descriptions of what the application does would allow me to understand what I am getting into, before deciding if it's worth it for me to pay that cost, and thus make an informed decision as to whether I want to sign in or not.
Having implemented Google Logins in the past, I always choose that option on sites I see: The site doesn't need to store any kind of password for you. This site also appears to be using the new Google "Cross Account Protection" feature, which will for example automatically log you out of the third party site if you report to Google that your account is compromised.
I think it was the point: the OP wanted to see more feature & screenshot before signing in, whether it's a Google login or not
So, I ended up not signing in, and, thus, I didn't learn how it worked.