Plants can be resilient to different conditions, though some of us find certain conditions easier to deal with.
As for your tomato, you say it is thriving in just water, but I don't see how you can say that if it is struggling to produce foliage and won't fruit. That's not thriving, that's merely surviving and it certainly isn't optimal growth, which is what most of us are after.
I don't know about GH grown veggies, since I haven't yet tried GH
nutrients, but my Miracle Gro grown plants in Coir are far more robust than the plants I raised last year in compost and soil. They also produce a lot more fruit that is much more tasty. They were from the same
seeds, so the conditions obviously played a role. It's not just about the breeding.
Even Miracle Gro will tell you that their product can be used in hydroponics but is not ideal. I know because I wrote and asked them myself. They recommend using other products in addition to theirs if using them in such a way because their solutions lack ingredients needed in a water environment for optimal growth. If optimal growth is in my grasp, why shouldn't I go for it?
I already mentioned I'm no good with soil and compost. I've been an unsuccessful gardener for about 15 years now. The only thing I can keep alive in soil is aloe. For me, everything dies of too much water, not enough water, parasites, fertilizer burn, or soil-born disease. I'm sick of the guesswork and all the time and money down the drain. For the last couple of months, I've been growing my houseplants in hydroculture and I've had a lot better success than I've ever had before. My plants are living and thriving. I've lost a couple, but my rates are much better than with any other attempt at raising plants. If I can improve that even more with established nutrients specifically for hydroponics, I don't see why I shouldn't.
I'm glad you're successful in what you're doing, but I have to be honest with you that I get the sense that you are rubbing my nose in it. Perhaps that's not how you meant it. As far as "you'll be fine with anything you use", I appreciate the sentiment, but 15 years of experience has shown me otherwise. I have an endless supply of rabbit and horse manure and I compost grain, fruit, and veggie scraps along with either dry leaves or dry grass depending on the season. I still can't grow healthy plants in soil or soil mixes. I'm done trying. I'm going with the scientific method and I think it's a little rude to scoff at people who do things a bit differently than you do.