My first Jaguar was a 1967 3.4S auto in gunmetal grey with blue upholstery. MAL 400E, did you escape being crushed? I bought it in 1974 and sold my Renault 4 in the thick of the petrol crisis, correctly believing that petrol would never be as cheap again. I was aged 22 then and, during my ownership, made the acquaintance of several young ladies who were tired of being thrown around in draughty convertibles or rusty, unreliable hatchbacks. That old beast could pick up its skirts and fly when required.
My next Jaguar was the one I have now, a 2004 3.0 S-Type SE in radiance red with cream leather, bought in 2018. Once again, I'm finding it doesn't show its years when keeping up with modern traffic and it's able to do the 500 mile trip from Yorkshire to my wife's family in Aube, France in comfort.
You can use and enjoy Jaguar class at any age you like in my view.