It’s thicker and heavier, to allow better cooling, better performance and better battery life.
I suspect the only reason why it's thicker and heavier is because of a PR-move aka. Apple telling us "we do care about the pro market". They could probably make these things thinner than the last 16" and still have massively better thermals than Intel versions.
Regardless, increase in size and weight are minimal over the last gen, display size is much appreciated and higher cooling capacity is nothing to complain about especially if you are getting the M1 Max.
With all that "thickness and weight" though these are still some of the smallest laptops on the market.
I mean, if none of this speaks of function over form….I really don’t know what to tell you.
This is not "function over form", this is "functional form", as Apple always did. Regarding keyboard and Touch Bar, well, mistakes happen. You try to innovate, something doesn't work out. If the butterfly keyboard did not have that fatal reliability flow, there is a good chance that everyone would be praising the fourth gen. butterfly keyboard instead.
Ports... as I said before, you trade one unversal port for a built in limited-functionality switch. For some people, this is more function (e.g. if you use the card reader frequently). For some others (like me), we now need to buy a dongle to connect our peripherals since we have port port less. MagSafe, well that is certainly form over function because it does not provide any additional function. Why do you need a charging port when USB-C provides charging? The only reason why MagSafe is back is because Apple is on the "blast to the past golden age" trip with these machines (notice how they resemble the old unibody models) and of course to appease the MagSafe fanbase. In fact, Apple did a great move here: they save money (no need to put additional PCIe lanes or Thunderbolt controllers),
make money (proprietary MagSafe cables) and make the pro fanbase happy. Look how much the former critics are renouncing for a 1mm ticker chassis and MagSafe, it's funny, really.
Personally, I would trade magSafe for the fourth USB port any time of the day, but I'm fine with the changes. The limited ports on the new models are a bit of an annoyance for my workflows, but I can adapt, and having HDMI can be occasionally useful when I am giving talks.