Having a side-hustle is especially interesting if you have enough free time on your hands and you need something to do. No need to walk someone else's dog if you don't have the time to do so and if you don't need the money.
If your hair is on fire with debt, then try to earn money in any which way you can. The rest of us, while we still work, should make sure we still have enough energy to do survive the working week and running our household without paying for a lot of insourcing. I find it challenging enough to find time for making dinner at home, clean our house, paint the house, repair the car, cut DH's hair, repair clothes. No way I'm spending my free time on being an über driver for low pay. When that it said, I do have a side-hustle now, but that is just a hobby thing that I did for free at first, that I am now getting reasonably well paid for to do a few hours a week. And yes, I would do it for free as well.
A side-hustle could also be a good investment, if it generates a passive source of income, like writing a book could do.