Why does Riot not let Silence proc Courage of the Colossus

Played a game today of ARAM before reading full Courage mastery. Was Garen so I thought I'd experiment with Courage. Just to be shocked that silence doesn't proc it. I'll be honest I didn't get Courage 100% look through and seeing the term 'hard cc' and knowing what that means to riot I understand now why it didn't work.

So I get what riots doing but I have to ask why silence isn't just not included in the courage mastery. (I've only had a time to research champions with silence, I haven't taken a look at the other forms yet, other posts may come later)

1. Silence is no different than any other cc except that I can move during it. (Functionally, its not making courage any more or less broken, in fact it allows more counterplay as I can still move.) I still couldn't cast spells in traditional hard cc(except maybe root and snare) and I can't in a silence which is also true.

2. Only a handful of champions utilize silence. My last check had the following: Champions with silence: , , , , , (on himself). Except maybe 1/2 of these (say..maybe , but he has a low base health anyway), I don't think this could be horribly abused in any way it couldn't already be. Almost everyone of these if they wanted to could use Courage of the Colossus could already. - Hooks, Knockup - Knockups - Fear - Suppress - Stun (albeit unreliably without help and usually not in the frey to make a huge difference) - (Can't do it to anyone but himself anyways, so who cares.)

So in essence, by including silence into the Courage passive, (not necessarily consider it "hard cc") we add yet another champion that can utilize it.

I haven't had chance to analyze the other forms of soft cc but I'd be interested on the champion pool that we really cut off in the distinction of specific soft cc mechanics and/or how broken they'd really become by allowing this mastery on them.

That isn't to say I'd fight for all types of cc being in this mastery. God knows I don't want the game evolving into everyone picking courage, but if a case such as this can be made for it where it opens it up to 1/2 that could probably use it and not overwhelm the current outliers with it, I guess I don't see why its not there.