I can't disagree with the hypothetical here because they are different states of play.
They could make a skill (or weapon group) as such; they just haven't up to now.
But that just speaks to a more robust gameplay in POE1. If GGG did make a skill gem(s) that only worked with daggers & an associated buff that would be fine. Largely because you'd have the means to support it in POE1.
Technically, unarmed in POE1 is functionally that- not so much the charges. But you have to use specific gems and equipment to make it work. And that's fine, because as mentioned you could support and scale it.
However, the way GGG did it in POE2 w/r/t spears is very poor. Even at the very most generous scale possible, needing to Parry for chatges to do a 5-6 button combo is sound in theory. In practice, its terrible damage, game flow and (frankly) exhausting.
I hit that Chimera boss with the full wombo--twister-combo and was doing about 10% more damage at best. That's bad.
Having to cancel and back out of a set up for the wombo combo is even worse.
Honestly, this action and collision based gameplay is not GGG's strong suit whatsoever. Just terrible, IMO.
- - - Updated - - -
For the interviews where Mark and Jonathan often say "That's a discussion we still need to have." about core elements such as accuracy, map sustain, or ARMOR, I would say they are still deciding what the vision is- yet alone who's.