Justice League plans for the villain have seemingly derailed since then, though, and with Titans casting its own Deathstroke, Bennett may be able to return.
One notable example was its ban on Slade Wilson for a time, which kept actor Manu Bennett from popping back on Arrow for quite some time.
Beyond actor and actresses’ commitments they may have to other shows, there’s also the fact that DC has a history of telling the Arrow-verse what heroes it can or can’t use.