For a full seating group, yes. It works as an accent, under a single chair, or in a reading corner, but a living room rug should reach the front legs of the sofa.
What size rug is best for an entryway?
A 4 by 6 suits most entries. Check that the rug clears an inward-swinging door, and choose a flatweave if clearance is tight.
Will a 4x6 work beside a bed?
Yes. Run it lengthwise along one side of a queen or king bed to land your feet on wool without rugging the whole room.