In what way is it dangerous? Thats what the fuse is there for.
Retired now, but been to many installations where the intake fuse had blown due to being constantly overloaded, if only by a small margin, but eventually, the fuse has failed. It's not dangerous, but it is damn inconvenient!
Norweb (to become United Utilities, then Electricity North West Limited) allowed me to unseal the main fuses so I could replace consumer units. Some older fuse holders were not labelled with a rating, but those that stated 100A did by no means always contain a 100A fuse. 60 and 80A were common.
And in older intake fuse holders, 40A was common. I have even found 30A fuse wire in a kosher DNO-sealed cutout!
Older houses have (by today's standards) smaller sized cables feeding them whereas today the modern cables are either 16 or 25mmĀ² for 80 or 100A supplies.
When we got our MG4, our meter was swapped for a smart one, but the old one was rated at 40A!
As for charging the car, my Octopus tariff used to do it religiously overnight but now will work out when it can charge whatever time of day it is.
The system balances loads too.