To be honest, I am not sure that the hand of god play was offsides! The final touch before Maradona gets it is not clearly a "deliberate play" by the defender. Maradona is not in an offsides position on the final touch by a teammate.

I'm sure that the offside law has been "refined" between 1986 and now, but this is the law as of today and there is a huge difference between touches by teammates and defenders:

https://www.theifab.com/laws/latest/offside/#offside-offence