Spindle-To-Pivot Distance

The stylus will mis-track, and you will get distortion, probably quite noticeably. Not good for your records and it will also sound unpleasant.

If your tonearm cannot fit on your turntable at the specified distance, you need to replace either the turntable or the arm.

You asked whether I have experienced this. The answer is yes. About 25 years ago I once fitted a Rega arm to a Project turntable in place of the Project arm. The effective lengths of the arms were different by a similar margin.
I didn't know much about tonearm geometry then and I wanted to see if it would be an improvement. It wasn't. The result was exactly as I described - mistracking and distortion.

So I can tell you from both a theoretical perspective and from experience that it is a bad idea.