Do speaker cables really make a difference ?

Everything makes a difference.

They have for me, and it’s audible.

The technical details about copper and construction, etc. are interesting and relevant -- possibly.

Why possibly? Because all these discussions about construction typically don't mention the more significant factors regarding when a technicality about cable construction becomes audible. In other words, what makes a cable design audible depends upon the acoustics and sensitivity of a particular (a) system, (b) room, (c) source, and (d) listener. Those factors are key variables causing some people to claim that cables are BS or that cables definitely make an audible difference.

For this reason, the deceptively simple advice to "try and see" is even wiser than it looks.

YES!!

Everything makes a difference +1

If though priority list was in order then interconnects and power cables have more influence than speaker cables.

+1, @audphile1 

I would look at manufacturers that are using PC-OCC copper in their speaker cables. Have fun!