It's important to define what the "Q" is.

4K QPS where Q = file uploads -> Definitely.

4K QPS where Q = HEAD request? -> Not so much.

Assuming most transactions are a largish file transfer it seems impressive. And I assume the transactions aren't evenly spaced, so the peak is likely much higher.

4k qps of DNS, for example, would be less interesting.

If it's a natural distribution the peak QPS will not be 4k QPS.

Impressive or not I just wish people would stop using monthly averages in the headline like this. You can't really make the case that this in-depth stack dive is for a layman audience, so you have to know what a meaningless metric it is.

The QPS is just a number, that doesn't say much. Impressive or not, it's still interesting to read stories like these. My nit pick is that they, like many others are only using one cloud provider, don't put all your eggs in the same basket.