From my personal observations, Google indeed hires a lot of generalists.
Source: been an SWE in a hardware org for the past year there, and my team is a mix of about 1-2 people with plenty of previous hardware experience and focus, with the rest being generalists without much previous related experience (including me) who can pick things up and resolve them quickly, whatever they are. Observed quite a similar pattern on other teams in the org as well, with the only exception (to a degree) being a few research teams filled with PhDs.
Specialist and fungible are contradictory. It's true that they don't hire specialists - but there are only 7-8 different software profiles they look for.
1. ML
2. Systems
3. Product
4. Data engineer
5. SRE ....
Are you implying most companies have 37 profiles? Even this article was giving multiple examples or a little Web shop that probably has less profiles than 7.