Yes.
The hw specs of both makes that imminently clear. Clock up, go 2x wide on memory, add DMA frontends to the hw functions, and make smarter stuff and there you are.
No, it is not a straight "upgrade" but you can easily see how the same thinking lies behind both. (I've heard that much of the C= 64 crew followed Tramiel to Atari and that the ST shares a number of quirks in the VIC-II chip.)
