What Tony Bacon says makes sense to me.
Trademarks for "trade dress" didn't exist back then, so there was no such thing as suing someone for making something you consider confusingly similar. To prevent a competitor from copying, you would have to have a patent on a whole design or some unique feature. Gibson didn't clone the JM or Jag design (if it were patented in whole) and if any specific feature were patented (e.g., the floating vibrato or the separate tone circuit) Gibson didn't produce that either. And AFAIK there's no evidence of any suit being filed.
Besides, the non-reverse FB/TB design looks more like the JM/Jag design than original reverse design! Plus, construction of either type was different from Fender.