Perhaps that's the case, but you could still theoretically look at just the original trilogy and go, "Yeah, this is good enough."
I'm not questioning his opinion (which, given my uncertainty towards FLCL 2 and 3 right now, I agree with), moreso the logic behind why they're unnecessary. I was also on the phone when I typed that, so if all else fails, it proves that multitasking just isn't my thing.