No it's not. So stop quoting it like it's some fact. Thanks.
No it doesn't. If people want to do WPvP people will do PvP. If people are using flying to try and escape WPvP, then clearly they don't want to do WPvP. Your argument here is a bit like saying that they should ban dildos because not enough sex is happening....
Introducing flying at the start of new content breaks exploration, that much is true. And that's a valid argument for withholding flying for new content. But it's not a valid argument for withholding flying indefinitely, nor does it support your assertion that "flying is a cancer".
The simple fact is that exploration breaks exploration. Once players have had enough time to explore new content, adding flying doesn't break it any further.
It changes the nature of the immersion. It breaks one type of immersion and replaces it with another.
A common fallacy that the anti-flying brigade likes to bandy about is that immersion is good. Yes, immersion can be and often is good for gameplay. But too much immersion can become a bad thing too. Why? Because at some point immersion has a tendency towards tedium. When immersion stops enhancing the gameplay experience and instead starts to detract from it, the game needs to actually find ways to break that immersion.
And travel is the perfect example of such a feature in the game. Travel is fun and engaging when you're exploring and discovering new content. But when you're travelling the same, familiar path for the 100th time, it's just a waste of time.
It helps players avoid an element of the game that has a tendency to become tedious over time (travel) so that we can focus our time and effort on the elements of the game that are still engaging and fun.
What you're failing to recognise is that the WoW gameplay experience is dynamic. Travelling between points of interest in the game is an element of gameplay which starts out fun, but becomes tedious over time. It's not because it's a badly designed element of the game, it's a function of how humans operate, that repeating stuff which is fun can become tedious and boring. Honestly, at this point in the expansion, if simply slowing the game down is actually what you're trying to achieve, travelling overland is no better than just staring at a loading screen.
Flying is the cure.
That's utter nonsense. Plenty of people wanted to be able to fly in the game since their first trip with a flightmaster and I can remember it being suggested from the start of the game. Also, the number of people asking for a feature that Blizzard never thought of first is a useless indicator of the merit of the feature. Most of the features that have been added to the game over the last 15 years have been less asked for than flying.
The only real problem with flight in WoW is how it interacts with new content. The problem with your opinion is that it fails to register the significant value flying adds to the game once the content is well established.