WD40 is no longer what it was, hasn't been for at least 20 years. It is only a namesake now. Water Displacement, 40th formula, used to be a good solvent and highly flammable, leaving a thin protective coating after gassing off, developed for Convair to use on missiles.
I used it frequently as a starting fluid for small engines. I have a couple old cans with a few drops left in them, and I can guarantee you the new stuff is not even remotely the same. It's barely even flammable, whatever it is. I don't buy any WD corporation products anymore, they have all been dumbed down to appeal to the average consumer. I now have cans of specialized products in my garage, that actually work.
I have no doubt that if you could get the old formula, it would be an excellent all around cleaner, lube, protector.
https://en.wikipedia.org/wiki/WD-40