First, I wouldn’t say never to a rescue tool (it was mentioned earlier to never use a tow line in surf zone) - I wouldn’t likely do it, but there are exceptional cases where using a tow line in surf may be useful. Corollary - there also aren’t things you would always do, exceptions may hold there too. Learn as many ways to do things and understand their pros and cons so you can choose the option that could work safely.
Tow lines are usually not used in surf zones because of the power and chaos of waves. Boats are going to get pushed around and even the best paddler won’t have full control.
The video @sing posted showed tow lines getting wrapped around boats. That is one risk. A boat wrapped with a tow line would definitely take away what limited control you had. And lines wrapped around boats, or even just floating around willy-nilly, adds to risks of entrapment. The reason the Greenlanders learned so many types of rolls was they were preparing for things like their harpoon ropes being wrapped around them when they capsize.
A more likely scenario when towing in surf is just that you probably won’t be able to tow in breaking waves. Thinking to a standard tee-rescue in flat water- as the rescuer maneuvers the boat around to the tee position, it depend on which boat is more “locked” into the water as to whether the rescuee’s or rescuer’s boat is actually doing the moving. If the rescuee is in the water holding their boat, it is likely that the rescuee’s boat isn’t moving to gt the boats lined up, but the rescuer’s boat is.
Same holds in surf. Breaking waves have huge amounts of power. Let’s say someone flips in the surf and the plan is to get them and the boat out to a safer area to get paddler back in the boat. Mixture of them swimming and a rescuer paddling into milder area of surf zone to pull them out, and you get the swimmer pulled out and put on back deck of a rescue kayak (swimmer carry). Someone else goes and puts a line on the front of the rescuee’s kayak and starts towing. If the rescuee’s kayak as it is being towed is hit by a wave, it will be grabbed by the wave and pulled back. As it fills more with water, the waves will have more grab on it. Very likely the rescuer won’t be able to tow it out, but instead would get pulled back into the surf zone. And those waves grabbing the boat will also cause huge shocks through the tow rope which could be uncomfortable at best, and if the resueer’s boat wasn’t in line with the tow line but was turned sideways when one hit, could provide a huge capsizing force.
In surf zone, if you can’t rescue in place I am more likely to get swimmer but let the kayak decide where it wants to flush to (often in to shore, but if it gets into a rip tide, maybe back out) and then deal with it. Here is a video from years ago where I was the swimmer and we did this - https://youtu.be/whdhKukvrAk?si=LQd1ktpH5yat6oP-
You had mentioned about tow lines in rock gardens. In rock gardens, it isn’t too different except the surf zones are usually much shorter. Less risks of using a tow rope, but risks still exist. I am not likely to use a tow rope to get boat out until we are past any breaking waves. To get past the breaking waves, I am more likely to do what I call a “throw”. I maneuver in so I am in line with waves (so I can keep myself in position and upright as the waves break on me). If possible, a quick drain of rescuee’s boat to make it move easier. I then grab the boat and “throw it” so it glides perpendicular to waves out past the break. Goal is to get boat past the break where you then have much better options.