Well, T'Pol tried to warn him early on, bringing up Vulcan protocols, which we know Starfleet eventually adopted. I was never sure what era the natives were supposed to represent. Early on, a sailing vessel seen from orbit is described as a clipper ship, which would mean at least early 19th century. But we don't see anyone using horses or buggies, just people pushing handcarts. Star Trek often made it look like domesticed animals didn't exist on other planets, for budgetary reasons. The equipment in the apothecary woman's laboratory seems to position the natives between 16th-18th century.
I can see flaws in the episode, since this is the first time I've been able to rewatch them since they originally aired. But I still liked the basic story. I wanted so much to like Enterprise when it started out in those early days, but the episodes I saw usually gave me a bad initial impression. This was the first one that didn't, though other people here seem to despise it, raving about earlier episodes that did nothing for me at all. I didn't even like "Broken Bow", but I never voluntarily gave up on the show.