Yes, if "the right materials" are used and the cables are treated "properly" (not bent out of spec, not too many connection cycles) then it's "OK", but those shouldn't be requirements designed into something that cost-conscious consumers are going to be assembling.
70 Celsius is NUTS for that usage, not ‘oh, that’s ok then’
It’s well outside normal expected operating temperatures for wire.
This data point isn't exhaustive, but it does indicate that the actual safety margin is not as tight as is assumed from this news cycle.
That brand new connectors and wire that are custom specced wouldn’t catch on fire (but come close!) at only 2x the power draw means it’s very likely any damage to a connector, wire, etc. especially with normal wire and connectors likely would cause damage and a fire, at much less than that power draw.
Which is what we’ve been getting reports on.
And that is just from minor physical damage it seems, ignoring corrosion or fraying wires over time which is usually the bigger problem.
The truth is the plug is more demanding and expensive than lower density options and it's dangerous when corners are cut. This is always true in power electronics, but the risk surface area is higher with a new and demanding connector.
Even with connectors and cables without those early problems, there are often longer term problems that show up over time - cables fraying at the connectors due to movement, plugs and connectors building up corrosion (and hence having higher resistance), connections loosening or getting bent, etc.
The link you posted, and your later statement seems to support the same view. I'm just repeating it so the folks dismissing this as just an issue with the badly designed adapters Nvidia distributed (in some cases?). It's overall a connector and spec that's on the edge of the performance envelope with some 'obvious' types of field failure modes that don't seem to be properly addressed.
Honestly, I'm a bit shocked they went with 'mountains of parallel power feeds' solution instead of... I don't know, doing 6 gauge stranded, which seems like the obvious choice to me? Parallel power feeds like this are always the source of endless fussing and headaches due to exactly the problems we're seeing. Trying to save a couple cents by using more of the same materials they have on hand I'm guessing?