Here's a potential workaround: Go to 'Illustrator > Preferences... > Guides & Grid...'. Uncheck or check the box for 'Show Pixel Grid (Above 600% Zoom)'. Click 'OK'. Select objects to distribute, click on a 'Key Object', then see if the 'Distribute Spacing' value now has a measurement label (.e.g. "in", "pt", etc.). This works for me using v24.0.1 on Mac.
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