Nope. There’s Helvetica Extended or Berthold Akzidenz-
Grotesk Extended, but no Arial Extended. I once suggested
it to David Saunders way back in 1993 who was then with
the Monotype Drawing Office (before the merger with Agfa).
I literally told him “Why not make an extended version of
Arial? The world can use some more extended faces.”
That was shortly after I had found out there were only very
few “wide” faces in the FontBook.

They didn’t follow the advice of a one-year-in novice at
FontShop Belgium, can you imagine that?!

Nonono, I’m not pulling yer leg, this is a true story, I kid you
not. This is SO funny you bring this up after all those years.