I feel the complete opposite. Olympics is only played every four years, it's also by far the biggest event in the world - surely it must be more special to win the Olympics than to win a Grand Slam? It's not even close.
Olympics > Grand Slams > WTF > Masters 1000
slams are bo5 from the beginning, olympics only in the final. it's much harder to win a slam than olympics. ask murray.
grand slam > wtf > olympics > masters 1000
atp/itf says grand slam (2000) > wtf (1500) > masters 1000 (1000) > olympics (750)