Text-based computing -> GUIs was a shift. Broadly speaking, there is no market today for consumer-facing computers where text is the only input capability.
The most profitable company in the PC era also has the most profitable PC unit today. The Internet runs on top of the GUI layer. The smartphone is (in much of the world) an "also" not an "instead."
(One could argue that the original MSFT goal of being on every desktop was centered on work. By that metric, most smartphone usage falls into a separate category of consumer computing that largely is distinct from business computing, where desktops & laptops still rule.)
A grandparent(-ish) post compares the iPhone to the Google Home. Much like the iPhone did not replace my laptop (which did not replace the server in the datacenter), voice-driven devices will not replace mobile phones. All Excel (ahem) at different use cases.