Actually I think banjo is coming back into vogue. I have played in a number of public venues this year, and was never asked to leave ;) Actually, I had quite a few comments from teens about how banjo was cool, and was a great instrument. People have stopped to listen, asked questions, and thanked me for playing. Even people in church have enjoyed having an occasional banjo accompaniment.
The gourd and minstrel banjos also have such a different sound that people take notice, and I've had quite a few comments on how much they liked the sound of my instruments.
The second Tuesday of every month, I hold a "Banjo Workshop" down at a local coffeeshop. I teach a bit, play a bit, work on instruments (restring, setup, tighten heads, etc.), whatever comes up. Been doing it for the past 5 yrs. The clientele seem to enjoy it and I always get compliments.
Last night, it was t-storm nasty out and when I got there, I first stood at the counter to get my cup of coffee. A young lady was ahead of me and asked the server, "Will there be 'banjos' tonight?" The server looked pointedly at me. When told her yes...she looked so disappointed! I said, "Are we too loud or obnoxious?" She looked a bit confused...but replied, "No, I have to leave in a few minutes and I'm disappointed I'm going to miss it!"
Similarly, I am doing an increased number of public presentations looking at the multicultural history of the banjo, primarily from ca 1620-1870. Many of my audiences are quite diverse (socially, racially, ethnically, etc.). I am pleased to report that there is definitely a stronger interest in people working to understand the complex history of the banjo.
To add some historical context and maybe validity to the initial statement, it appears the banjo has always been maintained by those of lower social and economic class (this is assuming the definition of a gentlemen is high social and economic class). The fact many people of the era knew the banjo was a slave instrument first colored their opinion toward it. Rigid social classes meant higher classes did not want to mingle with lower class entertainment, and especially not play their instrument. It seems only after minstrelsy gained world-wide accord were higher classes more accepting. In addition, although the banjo did become a popular parlor instrument, particularly of the late 1800s, it was sort of passed up for the guitar.
However, Today modernity has helped to spread banjos and recordings of it around the world. This website is a prefect example of permitting access to music that some people (in a life without modern communication and transportation) would never have heard. Nowadays, especially with changes in societal interactions and displays of class, anyone can pick up a banjo and not be scorned. My point being, playing the banjo was never as popular with higher classes as it was with lower classes--the Appalachian region being an example of this, as well as early minstrelsy in Northern cities, playing in lower class theaters. So, in essence, this statement rings very true, but it certainly does not describe all banjo playing and sentiments.
I was strictly assessing who might have played the banjo, not who enjoyed listening; I think that is an even murkier topic.
There is the story about the judge who was lecturing a group of law enforcement officials on a particular type of person you might see in eastern Kentucky. "If you see a man sitting down at the forks of the road playing a banjo, arrest that man, for if he ain't done something, he's a going to!"