Welderfag here…saw didn't do that. Look at the uneven lines, how its ragged. That's a plasma cutter and/or ocyacetylene torch. It's about as much news that those could burn through it as is is that water is wet.
Saws make straight lines, gas and plasma cutters make ragged ones. Pic for reference.
So, yes, you can cut a steel barrier…if you want to lug 200lbs of cutting equipment up to it. Good luck with that.