French style wine cupboard - Worth restoring?

Absolutely. You could not re-create that piece for less than $ 3K. It appears to me to be made of Heart (Longwood) Pine, you can confirm this by testing the density - if its resilient like oak or maple, then its Heart Pine. And that is a very costly, very rare lumber that was timbered out in the 1920's. If you wanted to make something out of that today, you would have to use reclaimed lumber.

It does not appear to have a finish on it. What it really needs is a good cleaning more than anything. You can use a good deck cleaner like Olympic brand and then follow it immediately with a wood brightener to neutralize the PH balance from the cleaner and it will pop like new. Then put a coat of clear varnish over it and it will look superb.