Well, that minimum font size wouldn't apply to SVG icons, so you're still not going to see them very well. So, it may be more effective to zoom the entire page overall rather than just font sizes.
Also, note that you apparently don't assign any culpability to browser vendors for the state of affairs. I encourage you to revisit that, plenty of blame to go around.
Sure. But that's an occasional need, while not enforcing a minimum font size means hitting C-+ a couple of times for pretty much every page I ever load. In any case, the icon-font problem has less to do with the minimum font size than with the enforced typeface selections, which necessarily and completely break icon fonts.
I'm not sure which portion, of the blame in question here, you contend belongs properly with browser vendors. There are lots of things they might do differently, but I don't see how this is one of those.
Also, note that you apparently don't assign any culpability to browser vendors for the state of affairs. I encourage you to revisit that, plenty of blame to go around.