I would agree that it depends a lot on the individual property. The previous owner of my house was a keen gardener and spent nearly 30 years adding compost, manure etc. I've been here 15 years and kept chickens, been adding more organic matter the whole time. The soil is in superb condition. If I look at some of the neighbours' gardens, the builders leveled the ground using rubble and then a few inches of top soil was added on top of that. Sure the date of last frost, amount of sun & rain will be the same, but not the soil. Obviously, you can improve the condition of it, but it takes time to do.
Equally, if I go a few hundred yards up or down the hill, it makes quite a difference - cold air sinks into the valley in winter and they get more frost. On top of the hill is quite exposed and windy and as the wind makes a measurable difference to crop yields, the farmers plant hedges as windbreaks.
Best advice might be to check out what's growing well locally?