Not that it's that much of an issue now that motherboards come with on-board-everything and a ton of slots already.
My cheap mobo got 2 * 16x, 2 * 8x, 3 * 4x (AKA M.2 slots), 2 * 1x, 14 USB 3.1 ports, 4 USB 2 ports, and I'm like .. seems like a waste to not have anything to plug in there...