Man I have had a significant number of games where I have had a robber block my resources to the point where my turn is just a roll and then pass... For like 4-5 full cycles. And at that point I am playing for silly self imposed goals or to allow the game to keep going for the other players... Not for my own enjoyment.
It’s not exclusively bad luck, but a combination of another player’s strategy and yours. You didn’t deem it important enough to have a Knight to defend against it.