Mostly it's a lot of the same things that could be done with a Opinel; opening boxes, cutting cardboard, food, wood sometimes. Thick-walled rubber hose was a thing that needed cutting at the lab at times, when the vacuum hose would get eaten by solvents.
It's not that an Opinel won't do those things, but I don't like the handle ergonomics for me; they just don't feel good in my hand.
I also don't have to sharpen a knife with S30V steel or Elmax or whatever as often, if run at a decent hardness, and while I don't mind sharpenng, it isn't the greatest source of joy in my life. I'd rather sharpen less often than more.
As for the type of knife, it could be the CRK Umnumzaan, or the Spyderco Yojimbo 2, or the ZT 0561 (which did a great job of cutting that couch up, saving me a $100 disposal fee :thumbup

...pretty much any of my knives that I feel like using at the time.
If I were travelling somewhere and for odd, unforeseeable reason didn't have a knife with me, I might buy an Opinel.
I'd probably buy a Swiss Army Knife with the saw instead, though; those things are handy.
It's not that Opinels are terrible, but they aren't
better at doing those cutting tasks either.
That's my peeve, when people claim that they do everything SOOO much better than the other knives.