Robertson on it’s own, yes. As long as you use the proper size driver before you round out the square.
When you start carving out space for additional drivers though, the screw head becomes much weaker. The combo Robertson/Slotted/Philips screw heads will not standup to the same forces.






Anti-tamper.
I’ve seen them used to screw together toilet stalls in public bathrooms. Stops bored crackheads disassembling them.