Heh, haven't heard of this but as a frenchie who sometimes hears swedes over the internet, I find that the permanent snus makes it sound like the person can't stop keeping some gum in their mouth, refilling mid-sentence because they really, really can't help it and it's more important than your interaction.

And so, having grown up hearing "audible gum chewing is rude", that sometimes feels rude to me. And it's not even in person!