Icons are rarely rendered at their intended size; there's a good chance that your browser doesn't render favicons at exactly 16px/32px, and a slim minority of Android phones have homescreen icons that are exactly 192px/500px.

This is why it's important to design icons that look good when passed through a variety of downscaling algorithms, and to test with other browsers/devices to make sure the icon comes out right.

Clients that download multiple icons can re-use cached icons with the same URL, which is why I re-used the 192px icon as the apple-touch-icon and re-used the mask-icon as the webmanifest's monochrome icon. Of course, I tested it to make sure it looked good when downscaled.

The master icon (svg): https://seirdy.one/favicon.svg

I made this icon specifically to have a tiny footprint (176 byte 32px favicon, 785 byte 192px icon) and to look good at just about any resolution when downscaled from the original, even on an e-ink display. I admit that my approach is a bit extreme, but most sites would benefit from something similar.