Now, magic can afford higher morals as well but it is also a rare resource and far more expensive that manual labor.
I appreciate most of your post, but I want to zoom into this point in particular and ask... is it?
I played a post-apocalypse game where my character was a Fey Warlock. We needed to grow food to feed the survivors from the city, which the DM thought would be a major challenge... but I had Plant Growth.
Plant growth is available at 5th level to Nature Clerics, Druids, Archfey Warlocks, and Bards. 5th level is not an unreasonably high level. And with this you can double food production in a half-mile radius, and that effect lasts 1 year. So, if you were to have a single mid-level nature cleric whose duty was to perform this ritual in the farmlands, and let us say he only worked half the year. He could empower the growth of 90 square miles of farm land, or 57,600 acres. which then would produce the equivalent crops of 115,200 acres.
Now sure, this isn't country-sized land we are talking about. It is much more of a county-size of land. But that is a single person, working for a divine power, for half the year. And even if you had 0.5% of 0.5% of a kingdom's population who were nature priests and reach 5th level... in a population of 1 million that is still 25 people. And that is just accounting for mortals casting spells.
There are good-aligned dragons, there are good aligned giants, there are celestials. Regional effects of certain dragons increase plant growth in a six mile radius, same with Ki'rin or the Cradle of the Hill Scion. Once you account for the gods, the fey, the elementals, the dragons, the giants, and then add long-lived races like elves, dwarves, gnomes... is magic actually that rare and expensive? How hard would it be for a Goddess of Agriculture to have her shrines be ritual sites where, as long as the proper rites are done every harvest, the land is blessed with Plant Growth? How difficult would it be for an Ancient Bronze Dragon who likes fresh fish to set up a magical beacon that increases the spawning of fish near his lair, which would just naturally cause a boost in fishing for the nearby port city? How many times do you need to have a friendly giant help establish an orchard of massive trees that grow massive fruit?
And yeah, these things can all break, they can all be destroyed, but that is sort of the point of having adventurers, right? And most DnD settings are ancient places, with magical artifacts all over the place. It just seems like it would be rather easy for all the immortal goods in the world to have left some impact on the lives of ordinary people.