It’s less a question of which is which, and more a question of what’s the context of the fight. There’s also some debate over which kills even qualify as ‘ganking’.
Ganking as a player-killing term mostly evolved from older games where a pack of players would basically insta-kill a much weaker group of players (or solo player). It then diversified to other types of insta-kill where there was no real chance of the target fighting back, such as thieves one-shotting farmers. It’s also mostly used, but not exclusively, in situations where the gankers can retrieve loot from the victim.
In EVE, that means ‘career gankers’, ie. the High Sec version where a group of them team up to gank targets for profit, are absolutely not “elite PvP”. Elite PvP implies winning a challenging fight with some risk of loss. Or at least outperforming the odds. High Sec ganking is generally undertaken with targets that are unable or unlikely to fight back (unarmed or AFK or completely PvE fit). So high-sec ganking is basically just another type of safe, risk-free loot farming, where the expense of losing your ship to Concord is essentially an ammunition/consumable cost.
Not all high sec ganking is of this nature. Some players ‘bait’ people into fights that look easier, then proceed to win the fight through better skill and preparation. Eg. Destiny Corrupted and others who bait players and then turn around and kill their attacker using their humble Battle Venture. Or some players bait/raid mission runners or DED complexes and thus are at least fighting someone with a combat (although still PvE) fit.
The same applies pretty much anywhere else, even though some people will tell you ‘ganking’ can only occur in high-sec because everywhere else it’s ‘standard behavior’.
If you regularly take on fights where you have at least say a 30% chance of losing, and you win most of those, I’d say you can call yourself an elite (or at least skilled) PvPer.
If you consistently arrange only to be in fights where you have a 5% or less chance of losing (whether by suicide gank, gate camp, hot drop, N+‘a whole lot’, or just carefully selecting targets that can’t/won’t fight back), then you’re on the ganker/PvP bottom feeder end of things.
Regardless of which security zone it is.