Many mini factors here, as it's a complicated global picture #
globalisation , but its primarily about currency movements affecting supply chain costs. Covid is a factor in those currency changes and the increased demand & fixed supply (also due to covid) allows Trek the confidence they can pass on their increased costs. Trek will hit the countries where they have the most demand first. Basic business 101.
The US dollar has weakened against the Taiwan dollar over
10% in the last 12 months ( an ongoing trend since 2016) - Trek pay a lot in TWD (they have factories there) and are looking to recoup that. I'd imagine that a lot of their suppliers for parts & shipping also pay in TWD so they will be charging Trek more. With demand at an all time high, all parties are confident that they can pass that on fully, to the consumer.
Without the currency shift we would not be seeing such big increases from Trek but we would be seeing some.
Its complicated as I mentioned - As an offset to their increased supply costs the Euro has strengthened against the USD by 15% meaning each Trek Bike in Europe earns Trek more but not sure what % of their market is in Europe. GDP to USD has been stable.
I don't think Trek are massively increasing their margins this year, but they are rapidly passing their increased costs on, which in a non covid world they might be more hesitant to do.
The Euro and the Pound VS the TWD have not fallen as much, so you might find Euro GDP firms (especially those making frames in China Or Vietnam where the exchange rate is stable) not as quick to jump on the price increase. They will be impacted by suppliers who produce in Taiwan, so it will come in some form...eventually.