I've seen braided wire used to bond lighting rods, and there are installation guidelines to avoid tight bends, etc, which I assume increases the inductance.
While these cannot carry a 1/4 million amps for very long, I'm thinking either the pulse is too short to do much damage, or that the ionization around it during the pulse allows current to flow through that
You always see how a tree explodes, or some other dramatic damage occurs with some strikes. This is the water in sap or wood boiling and is like a hot piece of metal dropped into a quenching bath and a violent boil occurs.
In another life I was interested in the microsecond events that occur when a fission weapon goes off. The expansion of the fireball from zero radius to the first few hundred feet goes through several different stages, with various degrees of opacity of the surrounding air and while one might think what goes on is defying logic, those with access to the data from such events can explain why it does what it does.
I'm all for finding out as much about nature as I can and want to know facts, as best they are understood by experts, rather than wave my hands and say there is some magical mysterious event going on. The problem with lightning it is hard to reproduce as it naturally occurs, and the calculations to determine air conductivity and resistance with micro scale humidity and particulate matter and many other factors make coming up with a reasonable model very hard.
Fortunately fewer people smoke nowadays, but if there is a very still room and someone has a cigarette burning, watch the smoke rising. The first few inches off the cigarette the smoke comes up relatively straight, but then it begins to weave back and forth and even fold on itself and split apart. The modeling of that air flow is hard. Sort of the same thing with lightning, I'd bet.