Filters in downconversion systems

one of the purpose of a mixer in a receiver is to perform frequency downconversion, by doing this, I've read that is easier to implement high-Q filters at lower frequencies.
Why this is easier than at high frequencies ?

first of all the Q factor of the elements u use to implement the filter high in low frequency so the Q of the tank circuit will be much higher in low frequency
also in high frequency the components become distributed not lumped

khouly