This is EXTREMELY difficult to accomplish, however, and usually only done by folks wanting "bragging rights". So called "century shavers" . . . in a practical sense, there is simply no need to be this fanatical about edge wear on disposable blades.

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I have seen what both a safety blade and a straight razor edge look like under an electron scope, and u/Berek2501 is correct. The "edge" is actually a line of "peaks and valleys" which, after contact with your hair, have the tips rounded off or over. Honing is done to "straighten" or realign those peaks and valleys and restore that keen edge. It's quite fascinating to see how "uneven" a truly "straight edge" is under extreme magnification.