Why would anyone compare a modern tpu against an Nvidia card that is four generations old? The tpu didn't even exist when the K80 came out.

Marketing.

nVidia is destroying the TPUs right now and Google is desperate to keep their perception in the public eye as the king of AI (which tbf, they probably are, compute capabilities aside)

You should try the assumption of good faith some time. It generally leads to a happier place.

In this case the data was from the time Google introduced the TPU internally, when the K80 was very much up-to-date. It also makes sense because the K80 was the only GPU offered in GCP.

This is the tpu v2, and it was most certainly not released internally when the K80 was.

You're talking about the tpu v1, not v2 or v3, so no.

Also, there's no need for assumptions when you know what's going on in the design team.

Google usually talks about it's hardware few months after they have moved to a newer better version. They probably are already using TPUv4 by now.

TPUv1 was never exposed externally as a thing you could rent in cloud, but with that exception, Google's been pretty consistently trying to offer the best available option to cloud customers.

(disclaimer: while I'm part-time at Google, this is my personal impression, not an official statement, etc., etc.)

They probably feel TPUv3 is stable enough to give access to cloud customers now. But I doubt they do not already have TPUv4 versions running already internally in some capacity maybe only for testing.

Since you mention it: Cloud TPUv3 is now available in beta (brand new!) See: https://cloud.google.com/tpu/

(420 TFlop/s, 128GB HBM)