Do please list me all those additional core abilities hybrid specs could get (You know, outside of stuff like Crusader Strike / Vampiric Touch).
Literally every single person i am discussing this topic dodges this question, because it just undermines your entire narrative.
Blizzard gave a lot of specs one set of abilities, you liked them or you could fuck off, additional options? Nope.
On top of that, this argument also applies to the old talent system, it's just one of those lies that the old talent system magically filled your bar with different abilities.