By the time it became clear that things wouldn't have gone that way, the west had bound itself to China too much to be able to do something about Tibet (without reshoring the manufacturing).
The Tibetan issue used to be felt very strongly, even in America, I believe.
It probably largely still is, but it's much less on the forefront, and probably seen as too hard to solve.
And maybe the younger generations don't know it well.
Anyway, if it became more feasible to improve the situation, I think there would be a lot of support and pressure to do it.
Sure, probably not to the point of entering into a war with a nuclear country, but that wouldn't be needed.
The support for Tibet was due to the fascination for the culture, the people and the places, I imagine.
People so peaceful, places so beautiful, and a culture so fascinating, violated in this way. It's just outrageous, and very hard to comprehend.
Of course anyhow, a reshoring anytime soon is extremely unlikely.
I'm not sure what you meant with the racial animus in the Middle East, by the way
Realism. Movements without a realistic goal tend to become quite niche, unless there's another hook to keep them going. With the rise of China as an economic and nuclear power, and one with no interest in even talking about Tibet as something other than a part of their empire, a populist movement to pressure politicians to "Free Tibet" is about as useful as a populist movement to get politicians to conquer the concept of entropy.
People, even very passionate and politically active people, moved on to causes with at least some hope, or at least the perception of hope.