For example, I'm using Debian, and I think we could learn a thing or two from Mint about how to make it "friendlier" for new users. I often see Mint recommended to new users, but rarely Debian, which has a goal to be "the universal operating system".
I also think we could learn website design from.. looks at notes ..everyone else.
I guess this has to do with the fact that BDFL Mark Shuttleworth after putting so much money into Ubuntu finally wanted to see some profit (I think I read that Ubuntu was not profitable for a long time) and went in the same direction like RedHat Enterprise and Novell SUSE had been going. If you look at Canonical Juju https://en.wikipedia.org/wiki/Juju_(software) launched 12 years ago, and things like Landscape https://ubuntu.com/landscape which has been there perhaps more than 10 years as well, and now with Ubuntu Pro it seems clear to me that Ubuntu was not just meant to be a desktop Linux distribution. In fact, nowadays when I try to find an iso file for an Ubuntu installation I need to be careful not to end up at a download page for the Ubuntu server iso.
Anyway, maybe I should instead try out and be recommending Pop! OS to new Linux users soon. It seems very popular https://pop.system76.com/ ;-)