Munchies:
It would be nice to at least be able to hide it.
This. At first I wondered if the top bar was merely being MOVED to the left side, and it was just in a transition. Nope -they intend to keep the top bar there to populate it with more icons.
Full stop guys, this idea is absolutely terrible. The only way to salvage it is to make the top bar non-persistent. That is, when you scroll down it doesn't stay there. For example, another popular feedism site that begins with an F has a big bar on the left side AND at the top. But the top one is just part of the page content. You can scroll away from it.
Making TWO always-there bars that you can't get rid of no matter what you do just made everyone's screen for actual page content like 30% smaller, and the browser draws it accordingly.
I'm not trying to be mean but it's not just a little bad, it's actually actively weird that you guys think its an improvement to make everyone's screen so much smaller from a design standpoint. It made me wonder if you are only testing this on a 27" 4k monitor and don't care about normal user scenarios? Because you need to worry about how it looks on a normal 14-17" laptop.
You can't just arbitrarily take away screen real estate like that. Then again, I guess you can it's your website...