For some reason I think of it as an older concept. Now Starbucks and coffee chains are popular.
Seinfeld on instant coffee https://youtu.be/uDrh5pujB9I?si=VdlVEREjMTNd2Bs7
Highlighting carlcook’s advice:
dissolve in cold water, ONLY THEN add hot water. The rationale behind it is that aromatics evaporate too quickly when the instant powder is infused with too/boiling hot water.
you don’t want to spend 10 of your 15 minute break making coffee with the aeropress. I have one and it makes fantastic espresso but it’s a giant pain in the ass to get one cup out of (to be fair I have never tried pre-ground beans I use a hand grinder with it so that might change this calculus).
I haven’t used it in years when I go camping I buy instant espresso instead. Only tastes 80% as good but it’s 90% less effort, mess, space used up etc.
I interpret your mention of pre-ground beans as an item that is bought, but if you need fresh coffee on the go you can just pre-grind them for yourself and take them with you.
I personally have an electric coffee grinder so my pour over is done in about five minutes, then I let it cool and take it with me in a thermos. Though I also only drink 1, max 2 coffees a day.