The belief most people have that Mozilla puts things in the browser they expect to be useful to users is mistaken and needs to die. They didn't decide you needed Pocket in your browser. They wanted Pocket in your browser, so that they could sell story spots (read: ads) to the highest bidder.
Note the PR-speak in that article. Advertising, by its very nature, cannot "provide value to users". If a publisher is paying to promote a story, it's because they want the story to capture more of users' attention than the users themselves want.
They discuss advertising in the browser chrome here: https://blog.mozilla.org/futurereleases/2018/04/30/a-privacy...
Note the PR-speak in that article. Advertising, by its very nature, cannot "provide value to users". If a publisher is paying to promote a story, it's because they want the story to capture more of users' attention than the users themselves want.