Right, so what we're shown may be inconsistent, but it's clear that some are being depicted like vampires, in actually taking physical damage from the sun. And otherwise, the plot has them not chase main characters into the sun because of an avid dislike for it in general, with the implication that some take physical damage.
In Syegfryed's case, he's been clear about talking about those who do take damage (the vampires) and calling that out as a creative depiction that he doesn't agree with. I mean, that's all he's saying really.
I personally don't think it's that bad of a depiction, and it could go either way and it doesn't really matter to me. The show wants to show them getting hurt by the sun, that's fine to me. They decided to make all the Orcs white or pale, that's fine to me too, and some people will hate that and that's fine too. I don't see reason to try and prove someone is lying when they're really just making the same points that we're acknowledging here; that the show DOES depict them taking harm from sun exposure, and that a dislike or fear of the sun is a reason why they don't venture into broad daylight even when their goal is slightly beyond their reach.