I'm not speaking to matters of style. These are matters of convenience. If one wants to carry a device around all day, one wants it to be light and to actually work all day.

I'm not claiming anybody wants a thinner phone. I do think few will choose a bigger phone or one with less battery life.

This race to the thinnest in mobile computing is going way too far for some years now, which sacrifices many things with no real gain: useful ports getting replaced by clunky adapters, modular components are replaced with glue, heat dissipation getting more challenging and finally loosing space for putting in batteries. You even regularly see oddities such as camera lenses sticking out of the back of a phone, leaving them unprotected, people putting their phone into cases because this thin things terribly fit your hand during usage and finally people carrying around external batteries all the time because the device obviously carries too little of them.

Additionally, pushing the device to the thinnest possible by not protecting the battery well enough was AFAIK the root cause of the problem at hand.

I completely agree. Is there any practical reason for this or is it just the best way these companies have come up with to try to convince people to buy a new phone every 18 months?

Except the note also accommodates a stylus inside itself.

Shame about the LCD. I'm never again buying a phone with an LCD display.