What is a "luthier" ?

The word luthier always seems to imply a skilled artist who makes musical instruments.
Yet the actual definition is simply "a maker of stringed musical instruments".

It's French for lute maker, just as a gardener is jardinier in French.
Because it's French it seems somehow a "fancy" term, like that person is highly skilled and maybe expensive.  ;)
But if we go by it's simple definition, then anyone who puts rubber bands on a cigar box and strums it could be called a luthier.

When it comes to mountain dulcimers, this is a relatively simple stringed instrument to construct when compared to violins or guitars. Cigar box dulcimers and plain box dulcimers are common. Even regular dulcimers are not necessarily complex to make and can be made with basic tools.

There are huge numbers of dulcimers that have been made since the 60s by ordinary people in their basement or garage hobby workshop. They put their names on them, using maybe a burning tool or a paper label glued inside. Many of these people made only one or two dulcimers and no more, as fun projects. Maybe they saw the article in Mother Earth and tried one out.

Years later, these casual hobby projects turn up on Ebay or in some garage sale, and the buyer is naturally hoping for a maker of historical interest. We look at photos, google like mad, and speculate if this was a known dulcimer maker (a "luthier") OR just a guy who made one dulcimer for his wife or assembled a kit and signed it. It can be confusing to put these ebay finds into one category or the other.

Going by the simple dictionary definition, are all stringed instruments made by "luthiers"?...even a cigar box with rubber bands? Is there a point at which a guy in his garage becomes a "luthier"? When does somebody become a "dulcimer maker" that might be put in a list of known dulcimer makers?  This seems to me to be a matter of degrees and subject to individual opinion.

What are your thoughts on this subject?  It might be fun to compare our views!