SLRs didn't have leaf shutters in the film days either. There's a few reasons for that. Firstly leaf shutters tend not to allow high shutter speeds unless you want massive vignetting, generally ...

Leaf-shutter lenses exist for flash use on focal-plane-shutter medium-format SLRs, with shutter speeds up to 1/1600s @ f/2.8; so they'd be possible for small-format cameras - possibly with full TTL ...