There is, actually. Just not on all machines. Typically there is a current sensor and you can set some pretty tight tolerances on what is acceptable under cutting load. This also helps to detect worn out tooling (though normally you'd pre-program this in advance, but there are workpieces that are so large they'll wear out the tool in less than one pass).

Not a direct response, but: adaptive toolpath (included in CAM programs like Fusion360) will make feed paths that aim for constant load on the tool, whereas more naive toolpaths will go from almost no load to extremely high load. On my crappy CNC machine it made a big difference in time/effort/money/waste.