Loneliness means so many different things to different people, so I'm not going give a "yes" or "no" answer here.
BUT
If the cause of your loneliness is being a member of a minority group (ethnic or subcultural), urban environments function as a great way to "find the others." (Though as the end of the article suggests, the Internet may relieve cities of the burden of this.)
I could see how being an elderly widow may be better in Boca Raton than NYC, and in this case, it's still a "find the others" situation.