Look at Finland, look at Denmark etc
Countries which are completely different to the UK in virtually every way, such as geography, industry, demographics, population, etc.
Population of Denmark - under six million.
Population of the UK - thought to be pushing 67 million.
Since 2001, the UK's population has increased by more than the entire population of Denmark.
How much more do you think it will increase in the next 5-10-20 years, where in the UK do you think most people will want to live, and what services do you think they will be most in need of?
Now you can either accuse me of racism, bigotry and xenophobia for asking the questions, or you can have a good hard think about how much money is going to be needed, where it's going to come from, and where and how it should be spent.