Yes. It used to show as a USB mass storage device, but a recent update changed it to use MTP (at least the Edge x40 devices). I don’t have my Edge here to check, but I’m like 90% sure you can also access the .fit files and load courses that way. It exposes a bunch of folders, including (I think) courses and activities. It should be possible to simply copy them to/from a computer that way.
This link is specifically about using Ride with GPS with Garmin over USB, but it should still be relevant (there is also a screenshot showing some of the folder structure): https://support.ridewithgps.com/hc/en-us/articles/12212969301147-Manually-Sync-your-Garmin
You do realise there are other types of holiday than flying around the globe to lie by the pool in a country with cheap labour, right? I think I’ve taken like one return flight in the last 10 years (excluding work trips). My last holidays I’ve travelled to by train to other countries in Europe. My next holiday I’m travelling one way by train and one way by bike.