Learning the language of the land not only gives immigrants confidence but it also opens them up to new ideas. How are they to understand that it's a woman's right to work or wear what they want when they can't even understand anything? The UK government has taken a good step and I think a lot of social tensions will decrease in the future.
When a person immigrates to a new country, especially if they are a refugee, it is important that they learn what they need to learn in order to function in society. For this reason, it's important for the person to try to learn basic skills that are helpful in the new country. Learning English is one of these helpful skills.
If the goal is to get individuals who wish to immigrate to fully participate in society and the economy, then the more effective approach would be to incentivize them. Rather than putting in place more stringent requirements for entry, the path to immigration could be expedited for those who choose to learn English.
No, requiring immigrants to learn English upon arrival is not the key to full participation in society and economy. Life in a new country is intimidating enough. Fear of retribution or humiliation over limited English skills might prevent some immigrants from participating fully in society. There have to be better ways.