youve left out alot of data.
the size and type of cutter, along with the type of cutting and material being cut will impact the feed per tooth. for example 2 flute 1/2 emd mills can range from .001 recomended feed in HSS to .04" (not a typo) on some fancy carbide ones for aluminium cutting.
2000rpm is definitely a limiting factor though and with typical hss tooling 40ipm would be optimistic on cutters under 1/2". you can certainly force the machine faster (ive done that by accident), but the tool and workpiece wont thank you and neither will the gears in the spindle head.