We don't need the population to grow but we do need to avoid a cliff-edge decline, which is what we are facing.
We need to get more people into employment and for people to start having more children.
Incidentally, about 3.5m on UCI are already in work, and there will always be those who very clearly cannot work, either because of their own health or because they're someone else's carer, so although our rate of economically inactive people is tok high, the idea that there are 10m people who just need to get a job is the stuff of fantasy.