It may very well be because of process too.
I don't like people calling out soldered stuff. By the way, soldered stuff may still be serviceable at 3rd party service centers, just not at every DIYers home. It will cost you quite some money, yeah.
There are laptops that have soldered RAM + Free slot for upgrade. But regulating that stuff is just stupid I think - there is a valid reason for manufacturers to try make things more compact, more streamlined etc.
Slots arw for upgrades, repair and salvage. Almost no nowadays notebooks with soldered RAM have additional slot. What of RAM takes 2 secocds with slot. Soldering lots of pins or reballing requires specialized equipment and skilled (and expensive) person.
I'm going to scrap 120 almost mint condition 8th gen i5 Thinkpads thanx to 8GB soldered RAM, which is no longer enough for efficient office work on W11 + basic corporate background apps.
With 1 fookin RAM slot, these notebooks would be perfectly fine for another 5-10 years.
What does it mean - scrap? Are you going to sell them? For how much?