What is classed as "elite" these days? I can certainly see a 2:05 marathon for Farah, perhaps a bit quicker. even if that is not really close to the WR it certainly would make him a major factor in an Olympic race - given his proven ability to get his best performance out on the day of a championship race and the fact that Olympic marathons are not run at WR pace.
Farah is far more likely to win another gold than approach the WR - whatever that will be by 2020!