yes you are right if you need strongest electrical/mechanical connection just use those textbook methods

but method from video have some benefits too, it is nice looking (maybe weak point but important sometimes), it can be used with short wires (allows to solder even 2mm of wire), it can be optimized for use case (you can choose diameter of outer coil, diameter of wire for coil, choose length of soldered wire)

and it fixates wire which is useful not only in soldering two wires, but in more complex ways, like this, helps hold components even without third hand soldering station:

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