I know that there are several questions related to the topic of conservative forces. But I am trying to understand where Feynman might have been coming from when he said that "We shall take a deeper view of this than is usual, and state that there are no nonconservative forces! As a matter of fact, all the fundamental forces in nature appear to be conservative." (link to lecture text: https://www.feynmanlectures.caltech.edu/I_14.html). I have seen this statement made in other classical mechanics courses too. While I understand where Feynman is coming from when it comes to forces like friction, I do not understand how this argument might apply on the electromagnetic force. In particular, the magnetic force is not conservative. So is there a way to think of the electromagnetic force as being conservative that I am missing somehow?
I would mention that I have also been through the previous discussion in this link: Are fundamental forces conservative?. In fact, someone links Feynman's lecture there as well.
The main answer explains that the notion of "conservative force" might not be important outside of a limited context. But I still do not understand how Feynman (and others) might have been thinking about this.