Oh wow you just reminded me threaded emails weren't commonplace until Gmail and I'm having horrible flashbacks.
Ok, so that's why people want threaded view? I've always thought that was puzzling, as I don't use it myself (neither threads nor Google).
Gmail might have gotten the inspiration after they purchased DejaNews and made the Usenet archive into Google Groups. Just a guess.
Usenet was always threaded in the clients I used back then. But for somme reason threaded email does not work for me, personally.
Gmail has a thing I don't know who else has. The emails are categorized in General, Social Networks, Ads and Informative Updates.
Like an email chain that keeps adding Re in the subject line
> Re: RE: Re: Re: Re: RE: Re: