Just to alleviate any concerns, the loan itself wont be 11 x salary, more likely average house price is.
There is no way any lender will lend 11 x salary to anyone*, as you say it’s insane. I’ve done mortgage affordability assessments for 8+ years and generally the absolute max is 5 x but that’s for higher earners & v v little outgoings. Many factors come into re the multiplier such as income and outgoings, term, location, house price etc
*technically BTL mortgages don’t adhere to this as the loan is based on the rent the property generates as it’s seen as a self sufficient mortgage.