Not sure if this is what he meant but you can call a bank or visit a branch, get a phone number for a specific department and call them directly and get almost VIP levels of helpful service in my experience.
Something that would entail hours of phone support thru official channels cut down to 15 minutes. Once you discover this there's no going back and it all depends on who you ask, and how you ask.
Even if they add it, the single-line display will always be around. It isn't mutually exclusive by any means. All clients that support multiline also have single-line support.
Thunderbird is finally paying attention to the UI side of things. Hopefully they finally implement the standard multiline email list view which has been on the back burner for 19 years XD