>>3202670>You are dumb
It depends on whether or not his interest in the ZS100 is heavily reliant on its zoom range. If he wants a compact camera with good image quality, the mirrorless with a prime pancake will give better image quality. If he wants a compact with a long zoom range and is willing to sacrifice image quality for that, then yeah, the ZS100 is the way to go.
I was upfront in my size response that the "not that much smaller" was with the caveat of using a pancake lens. It's not like I don't realize that a larger zoom range lens is going to make the whole thing a lot bigger, it's just not something that I personally prioritize and so the possibility exists that the Op doesn't prioritize that either.