I think your view on this is a little naive. Blizzard is a company that makes games, not a political institution that is accountable to voters. Its their prerogative whether or not they want to respond to the often passive-aggressive, contradictory reddit complaints. Some of the complaints that get aired by this community are ridiculous enough that they're not worth repeating, let alone worth individual responses from the devs. Some of the complaints are reasonable, and those get asked and answered repeatedly. If their response to the power creep question sounds canned, it's because it has been answered before, again and again and again.
'PR Answers' is incredibly subjective, and people tend to just say answers they dislike are 'PR Answers'. For instance he answers the Dr. Boom question by saying that Dr. Boom is absolutely not on the nerf list and that they don't like nerfing cards. That is an honest statement that reveals their philosophy about nerfs, so what do you think you would get out of 'pushing'? Should the interviewer ask, "But no really, I disagree, its OP, Pls nerf"?
Or to address that power creep question: he's pretty clear here, too, about his philosophy regarding new expansions giving new ways to play and not better ones. But you shouldn't expect him to outline specific plans about buffs, especially since they likely do not know them at this point. It's just not a realistic expectation of what a company would do, in my opinion.
Blizzard knows better than you or a community of 300,000 about the 30 million active hearthstone players. They have statistics that can gauge which features are used the most and which issues are affecting retention. And they definition have seen all of the common complaints and compared them with their stats. The problem with the reddit controversy culture is that people become convince their 1k upvoted rants represent us all. That is inaccurate, and blizzard knows this.
There are negative consequences when you view community interviews as controversy generators, as you seem to think is appropriate. That second article is the perfect example of the logical conclusion to your view: the interviewer DOES push (in an incredibly insulting way) an issue that Eric Dodds isn't even involved with and was not responsible for in any way. I actually cringed reading it. He's pestering the game designer about something the eSports division does and he literally asks if he feels 'regret' about it. At very least if you want interviewers to push you should acknowledge that it can be done in a much more respectful way, with actual knowledge of what the designers do.
In the end, if you really feel that Blizzard not constantly talking about their plans is some horrible lapse then, first, good luck finding a game company on earth with that level of transparency. No game company talks about their plans no matter how much people pester... its usually unnecessary, hype-killing and bad for business. But second, maybe you should stop following the community if it so deeply offends you. After all, in the end......