My 2-year-old golden just discovered he can drag me down the street

So Cooper has always been pretty good on the leash, or at least i thought he was. Then about three weeks ago something switched and now every single walk turns into a full upper body workout for me. He sees another dog and its like trying to hold back a freight train.

We've been trying the stop-and-wait method where i just freeze when he pulls, but honestly he just looks back at me like "ok, are you done?" and then lunges again the second i start moving. Ive watched so many YouTube videos at this point i could probably teach a class.

Anyone deal with a late leash pulling phase with their goldens? He's 2 so i know he's still kind of in the teenage brain phase. Trying to figure out if this is something a trainer would actually help with or if we just need to outlast it.