Exploration, when you want to fully scan a system or find something that is worth some money, worth scanning, and you have to travel 15 mins.
I mean, dude,
that's the entire point of that gameplay loop you're engaging with. That isn't pointless travel time, you're actively doing a gameplay thing in the game. Exploration is intentionally a "choose your level of engagement" tiered gameplay system, and each tier of it is more time investment for higher amounts of money and bigger details. Honk, FSS, fly to the planet and DSS, land on the planet and look for discoveries and/or collect Exobiology samples. Each of these is a tier that gives you a greater reward for investing more time in what you're doing.
The only part that can be considered "idle" is flying from the main star of the system to whatever you want to do a DSS scan of or land on. And traveling for 10-15 minutes (which you can choose to stop doing at any time in the process) is not the same as your previous "30-90 minutes of wasting my time in Supercruise" claim. If you're including the entire length of time you're doing exploration stuff as "wasting my time", maybe you're doing the wrong thing in the game and should find something more active to make your money.
I just don't see any value in making a player wait for an extended period of time, unless your business model is selling microtransactions in order to reduce wait time.
What microtransactions apply to travel time?! You can't buy faster supercruise or micro-jumps with Arx, you buy paint jobs and stuff. Nothing obtainable by Arx gives you any sort of gameplay related shortcut or advantage. What does Arx even have to do with what you're complaining about?
I used to have a tape loader, I don't recall loading anything for 10 mins, but even then I didn't have to sit in front of the screen for 10 minutes, waiting for something to happen. I got up, got snacks, went to the loo, and came back to a blinking cursor for me to type RUN.
If the problem you have is "I want to get up and do something else during my time supercruising through liminal space", they make this thing called a Supercruise Assist module that will fly the ship for you during the boring part while you go do something else. And in exploration gameplay, you're pretty unlikely to be unexpectedly interdicted on the way over. So... what's the problem?