Not many, if any, stretch 4s that shoot well that are worth a damn in terms of defensive versatility and rim protection. Maybe Holmgren??
On a team that's actually any good, usually those guys do zero outside of standing in the corners offensively or being used to pick and pop. Put Markkanen back on the Cavs, and playing with Mitchell, Garland, and even to a lesser extent LeVert, and he'd be doing that with his point production plummeting back to the 15-16 ppg he averaged when he was on the Cavs before being traded to Utah. While doing less of everything else you get with Mobley.