That's true but all the cool SMC-70 features, like the graphics modes, were custom to it.

CP/M programs written for other machines couldn't really make use of any of that unless they were rewritten specifically for the SMC-70.

If you just wanted the CP/M text compatibility and not the extended features you could buy a machine capable of that for much, much less.

As Kalleboo points out, if you wanted to buy off the shelf CP/M software you'd probably have to buy an external 5 1/4" disk drive too.