No, its not.
Sundance didn't have a choice, it was either he kept halo, lost money and lost sponsors and the business failed, or he didn't keep it and gain profit and have more prosperity, yes, you can probably say starcraft 2 could of kept that profit for halo, but, this is a business, and that's where halo failed, because Halo was no longer making that profit because of how much people didn't like reach, however, Sundance even said he didn't want to get rid of halo on twitter, but, he was forced into it by his partners and the sponsors, Halo was dying MLG Wise, and action had to be taken.
How will MLG fall if halo 4 isn't at the top? They have starcraft 2, arguably the biggest game in the world, how can they fall when they are filling events every time and earning huge profit? They didn't betray halo, they just had to let it go, same as they let CoD go and WoW Go, but, they don't complain that much. This is the time for halo to find other events and places so they can be popular and big like MLG, apart from have halo as the front of the company. (EGL, CGL, THC etc)
You make it sound like Sundance wants to get rid of halo cause he didn't like it, anyway, he says he liked halo 4, which is always a positive sign.
Forum wise, yes, we are their biggest supporter, but overall, no where near.
SC2 + LoL Own that title.