The bit I want to mention is what I call points of confluence (it probably has a proper name in navigation but I dont know it).
When there a point, headland etc that makes all, or many ships come into one point I call it a point of confluence. Its an area to be particularly aware.
This situation is similar. The OP and all the ships in the area are heading for one point. But to get there each may have a slightly different waypoints. We may all be steering 070 but still we cross paths.
In that situation I will hold my steady course. At 6 knots when a ship is 4nm astern doing 12 knots its stupid for me to do anything else. He needs to know my constant course so he can avoid me. How does he avoid a continually changing target?
Now getting back to the other general discussion that often comes up in these threads: ship fear.
I assure you theres nothing to worry about, only things to learn. There are so many busy ports around and areas where ships go that to take some advice you would need to transport your boat by land.
Looking at this photo below you will see, if you look closely 5 ships, and one has just gone ahead of us, you can see the wake (actually he's gone astern of us. Its a Port to Port situation). 2 ships are virtually superimposed on themselves and look like one. Theres no fear here! I had time to play with the wheel and take photos! No there was no bangy bits!.
Now lets have a look at this well known port. This ais grab is when I was heading up there the first time.
One NEEDS to be able to handle ships to make a run up here in a seamanlike manner.
Let me pop that one at you in another way: I think its UNseamanlike to be afraid of ships.
Go out and play with them and you will see its all A-OK.
Back to the OP: It was a flat day, both boats under power one clearly "stand on". Maybe the Captain of the ship was training a helmsman saying: "OK here's a safe situation, come a bit closer to the sailboat and I'll tell you when you are close enough for safety."
He would have been expecting a boat on a good, stable course going to a known point: a point of confluence not far ahead.