But the old meanings are all dead.
I’m sorry, but this is completely false. The swastika is still used all across the world for its original meanings. If you’d said this about e.g. Norse symbols like the Valknut or Sonnenrad, I’d be 1000% on board with you, but I’m going to go out on a limb and say you’ve not been to anywhere that Buddhism is common if you think everyone associates the swastika with Nazism.
There are specific versions of the swastika that Nazi Germany created that are only associated with Nazism, such as the 45-degree rotated swastika, or obviously any swastika embedded within another German military symbol, but to assert that the basic symbol itself has been co-opted is very Euro-centric.
Are you asking me to speak to this? I can’t speak to the personal motivations or viewpoints of either Native American tribes, nor of a myriad of Asian cultures. But I can say that I don’t personally believe it is either fair, appropriate, or necessary for Buddhists to stop using a symbol they’ve used for thousands of years in order to distance themselves from a group they are not in fact associated with.
I think you may have fallen prey to a false narrative around this. From what I’m seeing, the “whirling log” (the native american symbol that resembles the swastika) was mostly dropped due to pressure from white people over their own white guilt and the politics around Nazism, not out of some collective spontaneous show of empathy, and never actually fell out of use completely, and is now being actively reclaimed by various native americans.
It’s apparently still being actively used by the Navajo, as well, but they tend not to talk to white people about it since people can’t have a normal one.