I looked at your other comments. You live in north England and earn £20k per year.
If you have children, you will find that this does not go very far. If that is your sole income then your standard of living will not be far above one of the recent economic migrants.
If your children is not as academically gifted as you, they will likely live a life of chronic underemployment and a far lower standard of living than you.
It is the simple rule of supply and demand. Bringing in large amounts of economic migrants will depress wages and drive up living costs.
One or two generations ago, one wage would have been enough to afford buying a house in a decent suburb.
For our generation, you need two incomes for a similar setup.
For your childrens generation it will be three incomes as you will need to significantly contribute.
Every day in Nigeria close to 20000 people are born and this is accelerating. Even if 1% chose to come over, it is demographic suicide.
It is our grandchildren that will suffer the most. We are giving away all that we have worked for.