I'd say it's probably an even simpler explanation. Since she's back in Austria (and doesn't get out much) she's still not readjusted from Japan and isn't used to the fact that outside of Japans social autism people will actually greet you or say something more than "sumimasen" to people they don't know, or shoot bewildered gazes at the gaijin. A lot of folks that spend a good amount of time in Japan have that bit of culture shock upon returning home.
in the west maybe, She's got a pretty hardcore following in JP, those song covers of hers don't outpace most of her peers in views for no reason. (I say this as someone who keeps up with the weekly rankings on hololive music)
But Null, nowadays Vtubers
ARE the internationally infamous nigger-word sayers, the future is now old man