SD card support is largely meaningless to high-end professionals, few use memory cards and even fewer would bother with a built-in reader in professional work. There’s tethering (wired or wireless) for studio photography, cameras with built-in Wi-Fi and Bluetooth for when you’re on the go, high-speed SSDs or CFexpress cards for 8K 10-bit footage, etc.

Hobbyists, vloggers, even mid-range professionals (wedding photographers et al.) might use SD cards, but that’s pretty far from high end.