Tech support, a long time ago, in which the quick calls were extremely rare. Diagnosing a problem on the customers end or on our end, each took a lot of time.
I've also wasted hours of my life on hold with customer service "people" who, in the best case, take 5 minutes to hear my situation, 15 minutes to check into it, 5 more minutes to apparently not do the thing they said they were going to do, and 0 seconds to forget about all these details after hanging up, meaning I had to go through the same pattern all again the next call. Even in the cases where I've directed reps to look at previous tickets for history, half the time they still can't find it.
I'm sure that there are many people that use support instead of clicking around to the right option on the website, even though that seems abhorrent waste of time to anyone with half a clue. But companies optimizing for this are doing a disservice to everyone that is only using higher touch methods because they're trying to solve uncommon situations.
I can believe that "modern" support only takes a few minutes per the request, because each individual request is itself just a cog in the larger machine. When I spend an hour on the phone, bounced back and forth between 3-4 departments, how long was each of those conversations? Like so many things these days, the problem is with the overall constructive behavior rather than the myopic metrics that have been over optimized.
And don't get me started on those useless freeform voice prompts. Don't make the customer distill their problem down into a curt description, because once again, they're likely calling with a weird problem. Just give me the numeric options that mirror your business structure and I'll pick the most appropriate one, thank you.