I think it’s all part of the pendulum swing. A lot of early cookbooks were aimed at making the dishes of “your betters” and aimed at the proverbial housewife cooking an elaborate meal / course designed to impress friends / family / the husband’s boss, etc. And later we swung in the direction of “why do all this work when Corporate American Foods™ can do it all for you?” leading to endless canned, preprepared, or otherwise processed broths, sauces, mixes, et al. Then celebrity chefs and increased interest in cooking became a thing and the pendulum swung again - although as many went in the direction of seeking out unique establishments as cooking for themselves. And of course, the Covid forced cooking/baking craze had it’s own effect.
While I like to cook, and will absolutely look down on the lowest common denominator pre-made options (especially garbage store broth!), it’s really about what suits your combination of taste, wallet, skills, and time when it comes to the best cooking and food for you. But as stated in many of these threads, if you have the space, you can make good food ahead of time in larger quantities, and dole it out as needed with only minor quality compromises.
Spice mix? Buy the raw spices, prepare in large batches, keep much of it in the freezer except for what you’ll use in the near future, and you’re ahead in both cost and quality from what you’ll see in stores.
Stock and broth? Big batches in slow cookers or pressure cookers, strained, portioned, and frozen (and/or reduced to a concentrate/demi-glace) and again, you’re ahead of the game and almost always saving money.
And a lot of the tricks you learn from the books can help a lot, even if they don’t require time-honed techniques or a big budget. I’m not going to joint a roast, or start with the highest quality of ingredients man can buy, but if I’m making French Onion Soup per the OP, I can buy some meaty beef bones and roast them and some veg in a sheet pan or skillet prior to tossing in the pressure cooker, a small investment that’ll pay big flavor dividends.
Still, if all I had was a small loft apartment with a tiny stove and half sized fridge/freezer with minimal storage, you’re never going to have the same options.