Fair enough, in that case this is Digg v4 levels of arrogance. Tons of moderators depend on 3rd party apps to moderate [1]. These people are providing free labor on an industrial scale to reddit and it might be wise not to frustrate their work.
Reddit moderators are, by and large, terrible people. If they quit, as the guy in your link is threatening to do, they can be trivially replaced. It is not a thing that requires much skill.
There is no shortage of people who would volunteer for something like this. The replacements might even be less terrible, both at the job (reddit is stiflingly over-moderated, as documented on r/undelete and r/redditminusmods) and in their dealings with users.
[1] https://old.reddit.com/r/reddit/comments/12qwagm/an_update_r...