We have a labour shortage.
This impacts on productivity on whichever area you care to look at.
This in turn disadvantages others with lack of necessary goods/services, which in turn can create unemployment.
Hence migration worldwide, has historically enriched both the migrants AND their hosts, not least because migrants tend to go where the work is (obviously) and if the work gets done others get the benefit and it creates more employment opportunities.
We have a labour shortage - we need them.
Even without a labour shortage immigration tends to increase production, especially as they tend to be young, fit and highly motivated.
This is a short term, expediency driven view, and unsustainable as a long term strategy. The young, motivated and fit ultimately grow older and need the services which they originally provided.
Since 1997 (covering Tory and Labour govts) net immigration has been ~250k pa - total ~6.5m over 26 years. Over the same period total UK population has grown by 9.7m from 58.2m to 67.9m.
- housing completions have averaged ~200k pa fairly consistently. This is broadly adequate to meet increased population but takes no account of changing needs - family breakdowns, demographic changes.
- only an increasing real supply of housing will reduce prices and rents
- similar stresses in all public service provision - healthcare, education, fire services, energy consumption, water resources etc etc
- the UK is already more densely populated than other major European nations - Germany, France, Spain, Italy, Poland.
- net immigration has been a feature of the last 30 years and there is no reason why the trend should reverse. It is entirely structural.
One option is to accept the status quo. Future planning should very explicitly make provision for this population increase.
At present it does not. We also need to accept the indefinite price paid in terms of the environment, congestion, social impacts. IMHO this is not desirable.
It is similar to an individual continually spending more than they earn, covering the difference with more borrowing. This may work for many years. Ultimately there will be a reckoning - it is unsustainable. Expediency = bury head in sand and hope the problem goes away.
The alternative is planning to balance the workforce with the demands upon it through:
- training and education for those not optimising their contribution to society
- automation of services - AI, robotics etc
- improving productivity - stop that which is no longer needed (however painful)
- revising working expectations - retire later, more part time
Lip service is paid to this by both parties - it needs focus, money and resolve to make change happen. I don't see immigration as other than a short term stop gap whilst as a society we properly balance the provision of services with labour available.