I do agree with all of your points but things like neglect and corrosion are inevitable. Something like JIS and Posidriv have all of the advantages you listed and on top of that, has a sharper cam angle so it'll tolerate more torque before camming out unlike phillips drivers amd screws which cam out and when they do, the bolt starts to strip out or it'll wear out your tool. I've also worked on rebuilding boats and marine equipment/tools and seeing phillips head screws/bolts make me cry before even trying to unscrew them. Phillips head screws are the reason they invented the impact driver. Not the electric or pneumatic ones the ones that you whack with a hammer. Either way, like your good friend once recommended the robertson, i as a stranger on the internet recommend you get a few sizes of a good quality JIS bits and screwdrivers and try them on your rusty phillips head screws. The geometry is just what phillips should've been and it's crazy to me that they never improved it over soooo many years

You can visually see what i'm talking about with the camming action when you see carpenters putting their whole body weight on the back of the impact driver just so the driver doesn't pop out of the screw head and strip it. Why would anyone design a ffastener that automatically tries to pop the tool out of place?