It'll never be illegal. Just more restrictions in place. Speeding, DUI etc are illegal, but they still happen, causing so many deaths years. But they never resulted in cars being illegal.
Drones have become common now. News, websites, movies, TV shows, advertisements, real estate, etc are using drone footage. Emergency services also find useful applications for drones, as well as agriculture and other industries.
Fly responsibly, just as you need to drive responsibly.
What would most likely happen is that irresponsible drone pilots will be apprehended and charged, just like someone who's DUI or speeding.