BIMI: What does self-asserted mean?

What does it mean when people talk about a "self-asserted" BIMI logo, and should you set one up? That's the topic of my latest Valimail "Ask Al" video. A standard BIMI record does two things. It publishes a link to an SVG file, which is the logo you want displayed in the inbox. And it publishes a link to a PEM file, which contains a mark certificate (a VMC or CMC) proving that a certificate…