Let me give you the simple truth of this matter.
I have browsed /a/ since the beginning, I do so because it's the most active place to discuss anime with a lot of intelligent people who know more about anime than many.
I'm not into Toonami, I didn't care at the time - and I don't really care now as I saw most of the shows on it when they aired.
Some people see this short "Toonami revival" as a good thing because it gives more attention to anime. Others may see this as a bad thing for the same reason.
The reason people on /a/ don't like these threads is not for those reasons; the reason they do not like it is because they care more about the preservation and status quo of an online discussion board than they do about anime.
I love /a/ and as I said, I've been here since day one - but if /a/ was to disappear forever, I wouldn't really care that much besides where else I can discuss anime with like minded individuals.
A true anime fan cares about anime, not the so called "culture" of an imageboard. These idiots have an idealised image of /a/ in their mind based upon screenshots people have posted and a hivemind mentality they would be lost without. They are sheep defending their herd.
If you care more about the impact of Toonami on /a/ than you do about the impact of Toonami on anime, you do not belong here and should find a hivemind sheep-menality board culture elsewhere. I hear
>>>/b/ is a lot like that.