being dovetailed in is essentially worthless.
You left out the most important words, "To me", as in important to you.
Having the ability to shift the rear sight is essential for me. Also, it's part of the general trend of asking more and providing less, or, dishonesty in modern manufacturing.
I much prefer the all-steel construction of the Fort Smith models
Has Walther said this in print? If so I agree, and any time MIM is replaced with gun making materials that's a plus. My S&W PPKs ejector broke, which they immediately replaced with another cheese metal part.
(the PP Series is accurate by design due to its fixed barrel)
So are the barrel and sights on the same subframe? No, they are not, AND, the PP series pistols have lots of slop between the slide opening and the barrel, also, the slide to frame "Rails" are short and sloppy, a far cry from being designed as some kind of accurate target gun.
An accurate pistol, like the 1911 when well made, locks up tight as it comes into battery, the barrel is locked to the slide (And therefor the sights) in three or four places, and JMB decided slop was only needed for reloading each cartridge.
This is hard contact, unmovable steel against steel contact that repeats. The opening for the barrel in the slide of the PPKs is only constrained to center by spring pressure, same as the slide on the frame rails in the rear.
If your fixed barrel fallacy can be made to have truth it will be in a single shot pistol in which the cartridge in the chamber, the barrel and sights, and the frame, are all in one piece, as in a bolt action pistol or some breech block that repeats position the same with every shot.
Just because someone says a fixed barrel is more accurate doesn't make it so unless nothing between the sights and the bore can move relative to the other, and if the frame also is aligned for every shot and the trigger repeats with every pull.
So "accurate by design" is deserving of a jaundiced viewpoint, especially since the PP and following models were not designed to be especially accurate but to have average accuracy, which it does.
I have found my own S&W PPKs to be reasonably accurate, if Walther replaced the MIM I'm probably on board for one, and will cut a dovetail for the rear sight myself while cursing them for making me do that.