First of all did the semi have it’s chains on?
From experience, pickups are pretty worthless towing on snowy roads if there is no load in the bed over the rear tires. A big load of snow will work for that criteria though.
That is why my 4WD truck has 180 lbs of sand along with my 5th wheel hitch and a tool box in the bed. *
So far haven’t been stuck enough to open one of the bags of sand for traction. Did have to put it in 4 WD low going up the driveway.
* And yes, I have towed my 5th wheel in the snow. Did not want to have that adventure, but it was a very necessary situation to get out of where I was. I do have chains for all four truck tires and for the front 5th wheel tires.