Amazon

Ability to participate in community actions, like updating build tools to work with new languages.

It is easy to get help from another team, especially if you are good about networking.

The leadership model is open to doing things differently.

Builder Tools makes some really nice stuff.

Easy to become siloed. Easy to lose track of mission and take on too much ownership. Trouble tickets are not taken seriously. Quantity > Quality is enforced on some teams. Many core tools are very old and written in Perl.

The ownership of any product which is not under development or still managed by the people who originally wrote it should fall to trained professional operators such as Support Engineer IIs.

Other than that, I agree with team ownership of operations. It is synergistic for SDEs to support things, but only things about which they already know. Otherwise, it is nothing but a distraction.