The paragraphs from my article on pronunciation are:
"In medieval England, Stephen’s pronunciation varied, as surnames Steffens and Stevens both come from it. By 1550, almost everyone used the “v” sound in
Stephen despite its normal spelling with “ph.”"
"In 1940,
Steven began to boom even faster. That spelling overtook
Stephen in 1950 and has been more common in the U.S. ever since."
I didn't have room to mention it in the column, but it is true that there are many younger people in the USA who do not seem to realize that
Stephen is normally pronounced with the "v" sound and today interpret it as another spelling of
Stefan or
Steffen. There is now a widely known professional basketball player in the USA,
Stephen Curry, who pronounces his name that way.