I bet they are happy with paying £400 / month for rent, bills, the use of a car with petrol provided, laundry services, and all meals .
There are very few places in the country where you could rent a room in a shared flat for much less than £300.
Bills in a shared flat could be at least £60/ month, plus a share of the council tax for those who are working.
The Food for meals for most young adults would be at least £50 / week, let alone the cooking of it .
Plus a share of the cleaning for shared areas and laundry. And that’s before you factor in the free car.
So yes they are still being massively subsidised by their parents . Which is fine if you are rich and that’s what you want to do with your own money .
It’s less fine when they parents have less spare cash than their kids who are sponging off them as grown men . Or when the parents have to work longer hours or pay less into their pension, so their adult kids can have fancy cars / clothes / holidays.