The freeway will be there longer than you, and can only get busier. If it bothers you now it will be a negative for other people when you come to sell it. There are plenty of high end townhouses available both in and close to Los Gatos so make sure you have checked out all your options.
Good luck, Bill
Freeway noise does have an influence on buyers, not all, but many. That being said, most properties that are affected by freeway noise are offered at a price that would help compensate for that factor.
Keep doing your homework. Buying real estate is a very big investment. You want to make the best investment decision for you and your family.
All the best,