> It annoys me to get and send pdfs in text messages, but that seems to be how the world works now.

Do you mean PDFs for correspondence such as bills or invoices? That is not common for me.

mostly referring to pdfs to fill out and "e signature", my assistant sends them to me all the time.

In 1995 email was very common, but it was always a propriatory system that only could be used in your office. Very little was connected to an outside network.

We had an email system starting before I joined in the mid-80s (a product we made called CEO) but it was purely internal until well into the 90s. I'm not sure exactly when most people had some form of interoperable email but it was well into the dot-com era.

I still use email pretty frequently even if communications are at least somewhat fragmented across SMS, Facebook, Slack, etc.