Yes, technology has come far enough for Disneyland to offer this option again because flying is one of the safest things we can do. Flying avoids traffic jams and gets us from one place to another much faster. There is no reason that people should be banned from flying in.
While the 1968 helicopter crash was tragic at the time, enough time has passed for technology to evolve. If Disneyland reopened the helicopter option for arrival, it could really alleviate some traffic issues. Parking is such a headache at all of the theme parks, why not offer another option for guests?
Technology has now advanced to the point where helicopters are much safer. This means that Disneyland can reintroduce the option to have its guests arrive by helicopter without worrying about negative consequences. Back when they originally offered this option, helicopters were dangerous and people died. This is no longer the case.
No, I do not believe that technology has come far enough to make landing in Disney safe by helicopter. There are always risks associated with flying and these shouldn't be pushed just for a fun arrival to a theme park. The dangers associated with flying should be saved for when actually necessary.