Google is an ad company. Not a software company.

And AT&T was just a phone company that invented transistors.

AT&T, as Bell Labs, was a phone company that created the first working version of the transistor, a concept invented and patented by Julius Lilienfeld twenty years earlier.

But they were at the time, a technology company. Technology isn't defined by silicon and code, but by the fact that a company grows by inventing new things. Google may be on track to becoming an advertising company, but they seem damn resistant to the idea given how many of their new businesses they're burning through to find new revenue.

It's a technology company. Tech companies have been doing much more than just software for long

Quite misleading, one only needs to expand the FAANG label to see Facebook and Google the odd ones out.

10% time was an interesting idea, but have any valuable revenue generating products ever actually come out of it?

20% time is mostly used for side projects which aren't about coding or products anymore. But back in the day most new things Google was making came out of it.

Gmail, no? G Suite brings revenue.

It doesn't look like Gmail came out of 20% time, Paul Buchheit was asked to work on it so it looks like it was an assigned project not a spare time thing, and Google Docs was an acquisition (Writely).

Google news did iirc.