I think this is true but it's much more of an issue in LatAm countries where they drink mate through metal straws.
In european/North American countries where people normally drink out of ceramic mugs, people generally end up drinking hot drinks at a lower temperature
It's oesophageal cancer specifically, and I think drinking through a metal straw instead of sipping causes higher temperature liquid to be in contact with the throat.
Haven't actually read through the wiki references, but seems like it's an 'association' rather than anything definitive
In european/North American countries where people normally drink out of ceramic mugs, people generally end up drinking hot drinks at a lower temperature