Cables inside the smps often have some kind of strain-relief.
I have a manual hydraulic crimp tool, I have gotten cold welds with it down to 4sq mm, it’s really awesome. It was around 4000, which makes it the most expensive “hand” tool that I own:
There’s probably a reason why PSU manufacturers use tinned wire with crimped connections.
I think in their cost/reliability analysis, they decided that the convenience/speed of crimping is preferred within the time frame of their warranty, or lifespan of the unit, around 10 or 12 years.
And this makes sense, I asked an urban clap electrician about why urban clap has a service to replace internal wiring within walls (I assumed they were permanent), he said it becomes necessary after a couple of decades. I’m assuming this is the time frame for the insulation to disintegrate and the copper to become corroded/oxidized.