What I've got for our baseproject right now is something like

<pic src="@Model.Media" width="300" height="200" class="w-full h-full" img-class="object-cover w-full h-full" alt="@Model.Media.AltText"></pic>

which then would generate a element with sources in the ratio defined by the width and height. We use lazysizes for defining the sizes attribute, but I'm pondering of removing that, in favor of setting the sizes attribute manually.