I think he was unfortunate yes, but robbed would seem to imply that the race director intentionally waited for Lando to pass the pit entrance before throwing the VSC.
It's ironic considering what I said recently, that Lando does not manage anything. He simply goes all out when he has the lead. And here that backfired. Because if he had just been maintaining a three or four second gap he would have gotten the VSC in time to pit. I'm not saying that's what he should do, but if he had, he wins the race I think.