No, it doesn't. Simply having a cleric in the village who can cast Lesser Restoration completely rewrites medicine, expected lifespan, and the balance of power.I disagree with this, actually. This assumes that magical processes can be industrialized.
Actually, you don't even need a cleric in every village. It's enough to have one in the city, ensuring the nobility don't get sick and have long healthy lives (at the cost of being under the thumb of the cleric). Consider Rasputin. He had enough power, and he was a fraud. Consider if his powers had been real.
The common/rare argument is a red herring. The rarer magic is, the more powerful those who can wield it become. One real spellcaster changes everything.
Unless, of course, you handwave it away rather than try and work your way through the consequences. Which is what D&D generally does, and works surprisingly well.