Lope? Getting face hugged..? ...and the short time it's on his face?
Yeah, I can see how folks are upset by that.
That is, if they didn't give it any thought. I'm thinking the time in 'ALIEN: Covenant' is the normal elapsed time and Kane's experience was the anomaly. ...and it's all perfectly reasonable, really.
Kane's facehugger attacked him in an oxygen depleted environment. Of course it wasn't going to just hop off of him straight away. It was keeping him alive by staying on his face and feeding him oxygen, ensuring the host stayed alive for the duration of the gestation.
Lope by comparison didn't need the hugger to keep him alive. He was ganked in a breathable environment. The hugger didn't need to feed him oxygen.
It's not that hard, folks. Think a little. If you need to be spoon fed your answers, maybe Disney content is more your thing.
-Windebieste.