Anything requiring messing with about:config is an unreasonable way to treat non-technical users. And the point I've already made that you're ignoring is that the complexity of the workaround is not the problem—the necessity of taking action to disable Pocket is what was most concerning about what Mozilla did.
I found no value in Pocket and it was annoying to have to disable it once per machine but you didn't have to "live with it" as claimed. That's just ridiculously overdramatic.
I simply removed it from the toolbar, same as I did with the Firefox sync icon. Out of sight, out of mind. Granted, they were much more pushy about other features and services. Much less pushy than other vendors and it was, in some respects, understandable. (How do you convince people your product is relevant if they think it does less than the competition because they aren't aware of what's there?)