Not only Europeans... It is simply more comfortable, AC or not. But honestly I imagine I can just leave the battery pack lying besides me or wear some shorts or even buy some underwear with pockets (no way I'm doing this last one though) so it shouldn't be a big issue.
This is a very odd take. Southeast Asians and Louisianans work in conditions that are technically considered "uninhabitable" by OSHA. The response isn't working naked. It is not a use case that any company would consider primary.
Also, you know, you can always put on a belt without clothing.