Curt, That's what I was thinking. Though, I attribute this to the sparkplug design.

Cars of a few decades ago predominately (in the US) had cast-iron heads. It was the odd-ball VW's and such that had the occasional cross-threaded or galling problem.

Today, aluminum heads are much more common-place. As such, sparkplug manufacturers need to produce plugs with properly formed threads (after plating) with a surface condition highly compatible with aluminum alloys. . . .corrosion resistance while keeping electical conductivity.