If you want theories on why people don't care about the first delay; I assume that it comes from the fact that the expansion has enough content to sate peoples' appetites until the first mini patch? Like I said though, I don't think the fact that there aren't many complaints about that does anything to negate the complaints about delaying subsequent patches.
As for the problems, I'd say that it would depend on what the delay entails.
If it's a week-long delay on Savage? The most commonly stated problem that I've seen is that people just don't want to wait an extra week for something that they should be able to play on patch day. There are also people that are worried that it would slightly reduce the difficulty of Savage unless the devs go out of their way to tune for extra gear.
If the delay includes tomestones and crafted gear then that mostly fixes the worry about reduced difficulty. However, now you're delaying additional content that's usually ready to launch with the patch. When I have the time make a whole thing out of the patch day, part of my experience is running around and looking at all the new gear before I start going for tomestones/crafting. This would split the patch day into basically two mini-patches and I probably wouldn't have time to make a day out of both of those. So now you're affecting people outside of the Savage raiding community.
Is that a common problem to run into? I doubt it; and it's not a big enough deal to me to justify refusing a delay if it helps other people enjoy the story more. That said, it still negatively affects how I like to play.
So if your answer to these problems is going to be something like "Big deal, just wait a week" or "Who cares?", then you shouldn't be surprised when you get similar answers regarding the plight of competitive raiders. You may think those are weak complaints, but in this case, it's not really up to you to decide whether or not someone's issue is legitimate or not. They probably think that your complaint is just as weak. If you want some sort of constructive dialogue in this thread then we'll need compromise/empathy on both sides.
This is directed at a lot of people in this topic btw. I'm just using 2nd-person pronouns because you're the one that has been engaging with me.