Less than perfect English skills may not be an impediment to someone who already has professional credentials before emigrating to the US.
That is not the case if you are bright and hardworking, but without those credentials.
Perhaps persons in technical fields where human communication isn’t important can escape this general rule. But they are the exception.
Oh I agree. But everyone has obstacles to success in life. Language proficiency is only one, and judging from native English speakers who can’t speak proper English it is not as great an obstacle as it used to be.
People with less than perfect English face obstacles there is no doubt. But they can overcome that with other attributes.