Patents at work.
Before the patent on Phillips screws & tools expired, Pozidriv was launched which was different enough to be capable of a bit more torque.
Phillips was for mass-production, Posidriv for mass-production with a little more torque.
Lots of people who wanted that still waited until the Pozidriv patent expired before considering it.
The screws themselves are marked on the head with little ticks so you can tell the difference, but not necessarily the screwdrivers :\
It's good to have the right tool for the job, HP instruments used Posidriv in a number of places.
the type of screw head really doesn't make a difference when I'm hammering them into the wall, I've found xD
1. Dig out around the affected area
2. leave massive dent in the surface for what seems like years
3. Maybe cover it with a few janky bits of wood and/or metal sheets that make a hideous clanking noise all day and night and have the same approximate surface friction as an ice rink so are pretty murderous to any 2-wheeled road user
4. Leave this solution to mature like a fine wine
5. I really mean single malt whiskey. You can leave it basically as long as you like
6. There is no step six.