Yea for consumers these days, the physical size really doesn't matter much at all. ICs are small enough, nobody's looking forward to 5nm because of the physical size. What matters is cost and electric power usage.
The density improvements from 5nm absolutely matter and that comes from being smaller. If I can fit the functionality from two chips on one chip I save significant space on my board. Especially if the size of my chip is defined by the beachfront available for escaping IO. Not to mention all the supporting components required for each chip. And with half the chip turned off I can finally handle the power/heat issues.
We care about the TDP, which can be improved in various ways, not just moving to 5nm. Physical size in a phone or whatever is small enough, we don't care about smaller chips. The amount of space saved is negligible.
