No, of course daily PT isn't necessary - at any time. Your knee needs time and gentle treatment, so it can start to heal. Rest, ice, elevation, and gentle walking around the house are all your knee needs right now.although I do question if daily PT is needed 4 days out of surgery. These therapists really do have it engraved in their heads that everything must be accomplished NOW. And FAST. Why???
If your PT does massage to help reduce swelling, that's good, but the exercises aren't necessary.
The therapists want quick progress and rapid increase in Range of Motion (ROM) for two reasons.
First, that's the way they were trained - it's a bit old-fashioned now. Second, increasing ROM numbers are something definite they can record, to show how effective their treatment had been.
But it's not exercising that gets you your ROM - it's time. Time to recover, time for swelling and pain to settle, and time to heal. Your knee has the potential to achieve good ROM right from the start, but it's prevented from doing so by swelling and pain. As it heals and the swelling goes down, your ROM (both flexion and extension) will gradually increase.
You can go to PT and do exercises, or you can let your Activities of Daily Living (ADLs) be your exercise.
Your knee will increase its ROM either way.