Sure but that doesnt mean the smoke is useless. Just means the players are dumb.
Im always a B Anchor, my aim is shit ( i have shit reaction speed :/ ) but I managed to get high rank anyways with game sense & utility usage. Using a smoke B does almost nothing. Any team with a decent execute will just flash through. I mean hell most of the time you molotov they smoke themselves off so why would throwing a smoke stop them.
Its different for palace or ramp ofc. On B its much better to use your smokes for retaking A or smoking somewhere on site so you can play around it and try to get 2-3 kills for your team to win a retake. So a cross map smoke CAN be useful, i only use it like once every 4-5 games but thats better then nothing