Google first implemented Takeout like 10 years ago (Checking Wikipedia, in 2011). So they are more of the anti-example for your argument.
Now, as soon as Legal signs off, the production of the ZIP file is probably completely automated. And the programmers who made that possible probably believed their code was going to be used solely for their users' data portability.
(Disclaimer: Though I used to work there, all of the above is pure speculation.)
Its true that the Data Liberation Front did start as a group of 20%ers, but like the much less successful GMail, we got turned in a real team and now we have reorgs and TPS and everything.
[0] Check out the new My Activity service as an example of some of the new data we have added: https://takeout.google.com/settings/takeout/custom/my_activi...
[1] https://thejournal.com/articles/2016/12/09/google-unveils-gr...
Running a quasi-official blog without blessing didn't last either [0]. Glad to hear the team got turned into a permanent one internally, but the lack of a public info on its existence doesn't fill me with confidence that this is something Google wants or prioritises at a management level.
The gp was talking about companies' engineers writing "user-friendly data-portability features. Across all product lines". Is that the case with Takeout at Google, or is it just a job given to one relatively small team of self-starters working on a project that was never spearheaded by management?