From Wikipedia:

There has long been a popular belief that this was a deliberate feature of the design, to assemble aluminium aircraft without overtightening the fasteners. There is no good evidence for this suggestion, and the property is not mentioned in the original patents.

Edit someone linked this post from tool manufacturer tekton saying much of what I described may be popular misunderstanding, it may be worth taking this info with serval grains of salt https://www.tekton.com/blog/jis-vs-phillips-screwdriver-tip-geometry-and-fastener-compatibility?slug=jis-vs-phillips-screwdriver-tip-geometry-and-fastener-compatibility

If you like Philips aside from that feature (being self-centering is nice sometimes), JIS the Japanese industrial standard is basically the same design but its not intended to cam out, stripping the fastner

To my understanding you can safely use a JIS bit with a Philips fastner to reduce likelihood you strip it. But you ideally shouldn't use a Philips bit to turn a JIS screw. You can identify a JIS fastner by a little dimple in the corner by the plus shaped indentation

That's what op meant by "iT's A fEaTuRe"

There's a lot of history around the Robertson and Philips screw heads back when assembly lines were becoming a thing.

tldr: licensing is why Robertson didn't spread to the US.

Robertsons are the Pinnacle screwhead. Torx and hex are also acceptable

Robertson wanted to be paid for his good design. Henry Ford didn't want to pay, even if it was a tiny amount.

Ford was willing to use an inferior screw design that could cause production issues rather than pay a license to use the superior design. And, even though the patent expired a long time ago, these decisions have momentum.

I would bet that Torx is more popular than Robertson even though it's a much newer design. Is it a better design? To me, Robertson seems to have the edge when it comes to simplicity, but Torx could be better for industrial applications because multiple lobes that have a surface perpendicular to the direction of torque probably gives it more control. Also, thanks to Ikea, I'd bet that hex-head bolts are incredibly common. They share most of the benefits of Robertson. I suspect they're a little less efficient though because the closer you are to a circle shape, the less the faces of the screwdriver tip align with the direction of torque. I wonder if there are advantages of hex over square, since you see hex so much more often.

I’ve learned recently, by buying pozi head screwdrivers, that they’re not so bad. But it is unnecessary. Torx or Robertson please.

And half the time it came from the factory like that.

Phillips in electronics is what needs to die. They're always stupidly small and strip so easily

I'd ask how, but I bought my nephew his first set of tools for his 25th birthday. He doesn't exactly know how to use them (I'd gladly teach if I lived closer) but none of his blood relatives are mechanically inclined.

Still, better to have a plunger and not need one than to need a plunger and not have one.

Robertson drive thank you very much, that’s the pride of Canada right there.

Help me step-bit, I'm stuck and stripped!

I'm buying... Flathead...

Now see flathead is number two on my list of fasteners designed by dark forces.

Hex isn't much better in my experience. Torx is great though.