Tom Arnold has a good question ... why didn't Chyna's friends stage an intervention for her BEFORE her agent struck a deal with the TV show???
TMZ Sports broke the story ... Chyna's manager says in the weeks before her death, he was in talks to have the WWE legend appear "Intervention" -- but she died before production began.
Arnold -- a recovering addict himself -- says waiting to take action when it comes to substance abuse is a terrible idea ... because time is of the essence.