Ryan is a friend I made in Brussels. He's one of those diplomatic types. At the moment he is taking up homebrewing in Ghana, which will be worth a whole post of its own one of these days.
He sent his take on terroir and beer, and I shared it in the comments of the last post.
Interesting that so far the most skeptical comments on terroir in relation to beer have come from beer people. Then along comes a wine guy (who is now a beer guy too, I guess) who says, "Hey, that fits." I'll share his take again in a moment.
To back up just a bit: Don Feinberg proposed something called "monoculture" brewing. I'm not sold on that term for a whole bunch of reasons I'll save for another day (soon), but for now here is the basic idea:
There may be other ways to create a discernible character that sets a beer apart and above others but to me the surest way is
the house character that comes only from the combination of water, climate, brewery configuration and one yeast strain. This character, without exception, limits the styles the brewery can produce. But, when used successfully, it also
means brewery X can produce one style of beer better than other breweries.
I emphasized the word that I want to emphasize:
limits. I think that might be what resonated with Ryan the Diplomatic Wine-Turned-Beer Guy too. Here's his take again:
It is absolutely more than dirt and rocks and weather, although those are the influencing factors. Terroir is about the confluence of circumstances that, if a producer is interested in making the absolute highest quality product possible, force decisions which limit your options.

To get straight to the point: As others have noted (not just here but in many other discussions on this topic), brewers today have virtually unlimited choices. It has not always been that way, but as
Max said, the
process of brewing beer has arguably always offered more control over the final product (in relation to wine), thus making
terroir less relevant. I'm not sure anyone can dispute that.
But if brewers have unlimited choices thanks to a global marketplace of ideas and ingredients, then they also have this choice: They can subject themselves to some local limitations. It's a bold choice, and it's unnecessary, but I think that's the interesting possibility that Don is proposing. (And of course it's something that more and more brewers are doing all the time, to varying degrees, with the emphasis on local this or that.)
On the quest toward making the best product possible, a brewer can subject herself to the local limitations, forcing a whole bunch of decisions that lead toward a
distinctive product.
Now, if you want to get really philosophical, that is inevitably what happens to us as mortal human beings. We are not born into this world as blank slates, capable of being whatever we want to be. From the outset we get parameters from our DNA, our families, the cultures and institutions that bring us up. Within those parameters we make choices, sometimes just for survival, but ideally toward being the best person we can be.
One could argue that those limitations make things a hell of a lot more interesting.