We are planning to redesign the browser compat tables, and one of the things we want to do is have a “summary compat table” at the top of the page, that highlights obvious gaps in support, and links to the full table at the bottom. So I hope that’ll help with this.
That said, page design is IMO a hard problem. There are lots of people coming to our pages from lots of backgrounds and with lots of different agendas. Slathering the pages with banners for everything anyone might find important is a recipe for a mess.
One can start reading from the bottom of page, but would that be proper?
It’s intentional that the tables are at the bottom of the pages. The idea is that the easiest places to find things are the top and the bottom, because it’s always at the same location on every page. It’s the middle that tends to be the dead zone.