But let's apply some back on the envelope math:
In this PDF https://mtmmachines.ca/wp-content/uploads/2020/11/MTM-TP-Cold-Welding-R0.pdf it says that for cold welding to happen, you need to apply pressures over 12000kg/cm^2 (= 120kg/mm^2).
If you take a Molex KK-256 contact for example, the crimping area is about 6mm^2. For the cold welding process to happen you'll need 6*120 = 720kg of force on the jaws. Say you get a 1 to 7 lever effect from the Engineer PAD-11 (which is advertised for use with Molex KK-256), you'll need to produce a force of 720 / 7 = 103kg with your hands. An average man can produce 49kg of force by hand in his prime years. All this while assuming the Engineer pliers do not bend when they need to cope with these kind of forces. I hope this makes it clear that the engineer pliers are not suitable for reliable crimps as they simply can't produce the pressure required for the cold welding process. I hope it also shows why the likes of Molex, JST, etc don't supply simple crimping pliers for use with their crimp contacts; these won't create reliable crimp connections.
The problem with "back of the envelope" calculations are while they are excellent to rule out ideas that are wrong by many orders of magnitude, being too close the actual numbers and their suitability for the case starts to matter. So you say producing 103kg of force with your hands is a problem. It sure is, but is 10kg, which would be off by just 10x?
So let's question your numbers, 120kg/mm^2 is a worst-case number "as high as" for a process which has absolutely nothing to do with cable crimping, but is a complete different process namely making mechanically robust joints between two sheet materials. I can imagine the force required is higher as the materials need to flow into each other deeper than when the idea is to just make a gas-tight electrically low-resistance joint as in crimping (where the deformation of the lug provides the mechanical support.)
And sure enough, if you take a look at for example
https://uk.milwaukeetool.eu/en-gb/m18-force-logic-hydraulic-53-kn-cable-crimper/m18-hcct/ They claim they can crimp lugs for 300mm^2 wire. 300mm^2 wire lug has diameter of around 26mm or so, for a 10mm long crimp the surface area to apply pressure to is then 26mm*3.14*10mm = 800mm^2. Per your number, 120kg/mm^2 * 800mm^2 = 96000kg = 960 kN of force is needed to do that. Yet the Milwaukee only produces 53kN, less than a tenth of what you claim is needed. Does the Milwaukee live to its promises? I have no reason to doubt it. Now, can an adult apply 10kg of force with their hands? Sure they do, but doing that all day long would suck. Then again the Engineer product is not meant for all day long production work. I'm sure it survives the force of 100N for a long time, though.
So clearly the document which does not talk about wire crimping at all was not a very good resource, as expected. I understand why you chose it, though: it seems impossible to find any numerical data of electrical cable crimping pressure online. A lot of sources talk about how you should not apply "too little" or "too much", but no numbers.
Now I won't question the 1:7 lever ratio, from the photos it seems close.
Conclusion: calling something impossible by re-interpreting some numbers from completely out-of-context source is, while interesting, a risky business. I mean, all you need to do is to buy the tool and test it in real world use. Therefore I value the actual experience people are sharing, and the fact well known distributors keep selling this product, way higher than your theoretical back-of-the-envelope calculations trying to prove it would not work.
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