I'm reminded of a pair of interviews on Eurogamer.
Gabe Newell (Half-Life and Valve) followed by
Warren Spector (Deus Ex and whatever company he's currently at).
Essentially, Newell says "We like to design so that all our efforts are visible in one playthrough. Spending time on making six possible paths means the player may only see one sixth of your work. Bit of a waste."
And Spector replies in detail. Exact quote: "For players, a multipath/multisolution game offers the knowledge that if they're clever they will see and do things no one else has ever seen or done. How can you not want to play a game like that?"
It's interesting reading. I have a lot of respect for both fellows and it's amusing to see actual game developers gracefully tackle a common "forum topic" as it were.
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Anyways. If by "streamlining" you mean "increasing quality density", I'm all for that. Let's say the statistics indicate most people will "only" stick around for twenty hours... well, let's make those twenty hours bloody awesome? More satisfied customers, more money, more available games for us. (Contrast this extreme hypothetical with the opposite: they make a 200-hour game that confuses, baffles and bores everyone except for, let's say, half the people on this forum. The game sells twelve copies, Bioware gets stripped for parts and twenty-three people cherish the game forever while bitterly blogging about glory days past.)
And if by "streamlining" you mean "removing options" I don't object to that on principle. I honestly don't care if I have three dialogue options or nine. (Or none, though I highly doubt that will happen here, common slippery slope arguments notwithstanding.) I loved Planescape: Torment and I loved Mass Effect 2. The former was book-ish and the latter was cinematic. Both were great. But I should probably mention I've replayed ME2 five or six times. Torment, I've completed once and
restarted five times. This tells me something.
To bring this back to the OP:
You may be right about "inevitable". But while I have
opinions about the handling of DLC (for one, cosmetic changes and special weapons are not "pay-worthy content"; they're
horse armor and other phrases beginning with horse)...
I don't see inevitability as "doom". It's all just
change.