No, that redesign is horrendous. It follows modern 'design' principles of putting as little information on the page as you can and that's just a no go.
Steam's current UI isn't bad at all, everything functions and is similar to previous versions allowing anyone to find their way around comfortably. There are some issues, like in the older workshop pages and there is absolutely a lot of QoL that could be made, but the main store, discovery and library are all totally functional and nice imo. Steam having a slightly different style on different pages isn't actually a bad thing, at a glance you can easily tell what page you are on and makes it easier to find what you are looking for, whereas if it all looks the same, it's not as simple as they all become too similar.
Just because there isn't a shit ton of padding, doesn't mean it needs a redesign. Steam should definitely add skin support back though, for people who want to play around with it. I did personally use metro for the longest time.