Indeed. And then there is the design of the machine… In the photos of Usain Bolt, he is using a version of the “Hammer press” benching machine. Where you sit up and press horizontally. I find I can press significantly more weight here than a barbell, even though it doesn’t necesarily mean I am using higher c.n.s intensity.
But in a classic vertical smith machine, most could probably bench significantly more than with a barbell.
The fact that you can ‘only’ push 2.5 kilos more in machine (most could push about 10 kilos more), suggests to me that you probably have very good stabilization and adaptation to the barbell bench press.