The four-cup drip machine on the desk in your hotel room has not been cleaned. The pot has been rinsed, at best. The filter basket contains a light dusting of grounds from every person who's stayed in the room since the last real deep-clean, which — if you're at a chain business hotel — was probably last year.
The good news is that hotel rooms also come with a kettle. Usually a small plastic one in the coffee area, sometimes a metal one in the closet with the ironing board. Fill the kettle from the bathroom sink, boil it, ignore the coffee maker completely.
Then all you need is a mug (also in the coffee area) and a sachet (in your bag). Four minutes. Done. Cleaner cup than the fanciest hotel you've stayed at, made with equipment that was actually cleaned this week.
Bonus: the kettle also makes tea, oatmeal, and instant miso, so it earns its keep in a way the drip machine doesn't.