Why do turntables sound different?

Thank you for your thoughts.  I will go that direction then.

There is one table that sounds different from ALL others---the various incarnations of the Townshend Audio Rock. It is the only one ever made to feature damping at the front/cartridge end of the arm, rather than at it’s rear/bearing end. Though now almost impossible to find, Townshend offered it’s damping "trough" separately, to add to any table/arm.

I venture to suggest that quiet bearings are more important than low friction bearings. The two may not be the same. Although air bearings do seem to be best in both respects.

Also important is the resonance of the platter, especially in designs which do not use air bearings.

Just two of the considerations which affected my DIY.

Also, some tables apparently sound 'bigger' than others. Some sound 'bigger but slower', others 'bigger and not slower'. This observation does not come from my experience, I read about it.
I would say that my Spacedeck definitely does not sound 'small' and it is not 'slow' at all. Does it have to do with the platter mass and bearing?

I would suggest that quiet bearings would HAVE to be low in friction, period. The greater the friction the higher the noise. Greater tolerances also lead to higher noise levels. The lubricant will aid in reducing friction between two surfaces, but in thicker forms can raise drag in a design (flaw) that may require such to lessen fluctuation noticeability and to lessen the effects of greater tolerances , i.e. , grease. The platter needs to drain, not reflect back to the cartridge.

Your Spacedeck, of the few I have personally heard is more a lively sound with good detail with the cartridges that were installed on them. Heavier mass tables sometimes (not always, try to avoid generalizing as their are always exceptions) don’t play the subtle details as forward that gives the appearance to some as slow. But to the next guy, they sound correct. One thing to remember, ears don’t function the same from person to person. That’s why we have choices of different styles and sound and what music type will also have a factor in the equation of choice as well.