I should clarify, that IF you are complaining about how much magic costs, then you shouldn't be playing. If you want to play casually, then cost isn't nearly as much of a factor. It's the people that want to be competitive and own all the cards, but can't afford it, that tend to complain the loudest about prices.
I work at a game store, and I see the casual players all the time. They raid our common/uncommon box or bulk rare box for practically a full deck, spending a total of maybe $10 in the process. But, it's just to play against their buddy who is standing next to them doing the same thing. They'll do that once every 6 months and be fine. More power to those players, and they make up a significant portion of the magic playerbase, they just aren't very vocal. They don't post on forums or generally associate with other magic players other then their little play group, but there's tons of them out there.
WotC's development cycle IS very long, but making small last minute tweaks can be done, sure. That's two separate things. But, using the most hot button example, the player base has asked for fetch lands and they agree the price for entry to modern is too high. When did they skyrocket? Within the last year. Ok, so should they have thrown them into Theros? Hell no, then we'd have shocks and fetches in standard and it was largely finished by that point. They can't throw them into m15 either for the same reason, though a much shorter time period, and they may not even show up in Tarkir since it might not fit the theme that the entire block is built around (though, I kinda think they will, or we'll get a Modern Masters II announcement). So, if that's the case, we wouldn't see them for another year from now, at the earliest. That set is also being fleshed out in R&D as we speak, and they aren't going to shoehorn in something that doesn't make sense, or scrap the entire rest of the block's themes so that it does either.
They start working on sets more then 2 years in advance, and if a problem arises that they didn't foresee, it can take two years for a natural fix to come out. If they just start panicing and throwing band-aids into sets at the last minute, without proper testing, then it has a higher chance to cause a chain reaction of more problems
I will say that I sort of forgot about all of the MTGO bullshit lately, as I do not play MTGO. I do not play it, because it's a shitty interface, so I do agree that MTGO is pretty crap. That's the one thing I don't understand, why they aren't willing to put the money into re-writing the game from the ground up with a better programming team at the helm. Playing a game like hearthstone and then trying to play MTGO feels like a timewarp 15 years into the past of computers.