They made some pretty good barrels. I'm sure the various solvents and fluids used in manufacturing made it a smart choice to just keep the fire contained.
Most of the large machinery will not be all that damaged by fire.
Might lose a few motors and smaller items though.
Control knobs and stuff like that are usually pretty easy to replace.
Cast iron is pretty safe in fires.
I had a mill that was sold off as scrap after a fire.
A couple new motors (main and table) and it was back up after only a few weeks.
Tool longer 30 years ago to find all the handles and hand wheels.
That stuff is not nearly as hard to replace now.
Some really old stuff can require adjusting of new parts to fit.
Not all of it is what we consider 'standard' now.
It was actually easier in some cases to cut center hubs from the
old damaged hand wheels and fit them into new hand wheels that had been cut.
If you want to start salvaging by a barrel of WD-40 and start covering every inch of cast iron with it, followed by some gear oil.
Rust can damage precision ways in very short order.