This is the problem. Your guess is different from the author's guess, because nothing is explicitly stated.
For others who did not click the link, the explicit requirements are:
> - Email client can either be in the terminal (i.e. a TUI) or a web app
> - Should have basic email viewing + sending functionality
> - Can use a fake backend (DB, in-memory, etc) or real IMAP/POP/JMAP/etc backend
> - Does not have to handle rich text messages, just plaintext
> Your implementation should take inspiration from existing terminal email tools like aerc, mutt, or even something like himalaya.
It should feel fast and intuitive, and you can choose which email flows you'd like to implement.
The word "keyboard" does not appear. Inspiration from X, Y, and Z is entirely subjective, and you should not be punished for not reading the interviewer's mind.
Is it not clear that every single one of the example apps the spec cites are text-based UIs, as in curses-style, monospace text, and (yes) keyboard-driven?
My takeaway from that is that if you don't make an app that is (quote) "in the terminal (i.e. a TUI)" but choose to make a web app, then it should look at act like a TUI.
What I got from that is "fast and intuitive" is the must have. When you have a choice (backend bit), justify you decision. I'd try to use that to stand out or an additional cool feature. When I have to do such homework, I do the requirements to what I think an above average candidate would, they've seen this a million times, then add 1-2 bits of flair/coolness only a handful of people would do to pique their curiosity and want to ask about the next round
The youtube video provided by the OP seems more "web-app", "click driven".
For contrast:
* The OP's submission: https://www.youtube.com/watch?v=yY1sVXMkP_o
* Someone interacting with aerc: https://youtu.be/kpAwwgnZUxg?t=308
* Someone interacting with mutt: https://youtu.be/C35NRp42bEQ