The shift from BPF to eBPF was less of an evolutionary step as the name might indicate. The overlap with the name BPF is primarily due to the requirement for eBPF to be a superset of BPF in order to avoid having to maintain two virtual machines long-term. This was one of the conditions for eBPF to be merged and in that context, the name eBPF made sense.
Disagree (see sibling post). Classic BPF could have been translated into any virtual machine design they came up with (because classic BPF is incredibly simple). When McCanne came up with the same design in 1998, his team called it "BPF+", for the same reason eBPF is called eBPF --- because it is pretty much an evolution of the earlier idea.
