Exactly. If the problem was note-saving integration, they should have built an open interface for it, and then maybe (maybe) endorsed Pocket as the reference implementation, featured in the extension gallery or on the start screen.

Bundling Pocket outright, like Mozilla was just another Silicon Valley company, was very shortsighted.

Almost like you could install Pocket whenever you wanted to use it in your browser and remove it when you didn't want it, like you can with search engines?

Also, I would not particularly call those search engines a great comparison. They are simply keyworded bookmarks - you set the URL and when you enter a character or click the icon it loads the bookmark. The extent of integration was the search options menu where you can add any website's search field and it inherits the icon from that website, so its generic.