You’re correct - I went back and looked at the charts after my post and realized I had completely forgotten some of those others. Not a huge body of work, but certainly not the 1910 Fruit Gum Company, either. I was also unaware that he’d recorded the Hank Williams classic.
Well, he wasn't Hank Williams, but B.J. Thomas's version is pretty good. Thomas had an excellent and distinctive voice (think back to "Hooked On A Feeling").
And he may have had a huge body of work but across all Billboard Charts he had six #1 hits. The Beatles only had twenty #1 hits, all in the Billboard Hot 100. Elvis had only twenty-one - but unlike the Beatles, he spread his #1 hits across country, adult contemporary, gospel, and Hot 100. (Yes, George Strait has something like 57 #1 hits, all in country).
And Thomas recorded 51 albums, which isn't a paltry number.
Were we talking about Butch Cassidy?