From my experience, Windows does freeze and become completely unusable too, just not usually from RAM usage hitting 100%.
I don't use Windows much, nor do I care much about that environment, but from what I've seen it seems to keep RAM usage below 100% most of the time. What I do see pretty often is the drive getting stuck at 100% usage instead, which makes the whole system ridiculously unusable anyway.
Haven't had Windows freeze on me for ages. I had a frozen linux server that ran out of RAM yesterday.
Use a windows server then :D
edit: I meant that regularly hitting OOM on a production server is usually more of a provisioning/resource-management issue. Obviously, how the OS handles OOM once it happens is still its responsibility.
Running out of memory on a linux server sounds more like a skill issue than something comparable to how a desktop OS should behave :\