When I saw the title I initially thought it was about the advanced age of the average Jaguar owner
However, replacing the carpets is likely to be an improvement, especially if all damp underlay is replaced. The key to retaining the, shall I say ambience rather then smell, is to use Gliptone Liquid Leather regularly on the seats. This will keep the leather supple and smelling just like a Rolls Royce, sorry, Jaguar.
Al