Does remote control degrade the sound of tube preamps?

There is nothing that makes remote controlled volume control inferior in sound quality.  If it is implemented with a motorized potentiometer, the quality is entirely dependent on the quality of the potentiometer, not on the motor whose only job is to twist the shaft just as your hand would also do.  Even if your volume control is a rotary step attenuator, it is possible to physically move the dial under motor control (Ayre does this).  Many very good attenuators are ladder step attenuators that are switched by relays, and the relays are always remote controllable.

It is so important to get volume set just right to get optimum sound quality and satisfaction, and that can only be done practically by remote control as you sit in the sweet spot and instantaneously hear the result.  Remote control of volume is pretty much an essential feature, not merely a convenience.  Without it, one tends to just live with something close to the right volume instead of actually determining what is the right volume.

And they look cool when the knobs move.
It is pretty slick (IME).

I had never seen one until I got a used preamp with this sort of remote, and I like it conceptually and also in action.

As a manufacturer we tried so many controls and recently replaced a very high priced control $400 that we added Audio Note resistors to with a basic ALPS, darn if we could really hear the difference.  BUT I an sure there are difference depending on what your system can show.

I doubt I'd hear any difference at all, and the convenience of having the remote would far outweigh any miniscule difference there could possibly be.

I've got a Herron Audio tube preamp, and I think at one point, Keith Herron did not offer remote, but there was enough demand for it that it now has it. For a great, great product, this is the cheapest remote I've ever seen in my life - all plastic, weighs almost nothing, and it's less than 4" long! Gets misplaced very easily, too! Maybe this was Keith saying 'OK, I'll give you a remote, but .... '

It seems that the consensus is that a remote will not result in an audible degradation of the SQ. Thanks to all who have posted.

I have Coincident Statement linestage, dual manual transformer volume control. They offered stereo volume control via remote for a short period, inferior sound quality vs dual mono. In some cases, this linestage being one, fully balanced, even to extent of volume controls, any blending of two channels will negatively affect sound quality. With total mono even through volume control sound staging is more precise, and center images are absolutely locked in, stable. MkII with even better volume transformers and my added Amtrans selector switches, extreme precision  switches only add to this precision.

Bottom line, volume controls come in many varieties, remote may or may not impact performance. IME any balanced pre using stereo volume control is compromised to some extent.