What more should they do?
Also note, Red Hat pays engineers for the extended support, the compliance https://access.redhat.com/articles/2918071, etc that customers expect from RH. Engineers contribute both upstream (first) and backport those changes to older releases.
They're paid to work on FOSS projects. Gnome isn't a RedHat project. Nor is the kernel. And they're IBM projects even less.
And most of those projects started without RedHat and RedHat stepped on them to become what it is first. Plus, there are thousands of essential projects they don't have anything to do with, still in the distro.
That's one of the benefits of open source. It helps small guys to get started and make it big. Once they become big, they can contribute back.
Contributing starts from day one https://old.reddit.com/r/redhat/comments/14jq5i7/red_hats_co...
You can't all of a sudden expect you to have gained respect and trust, just because you are part of something 'big'.
I'd appreciate a small community more when they reach out, to grow them, than for a big one to lend them a hand with the basics.