Facts:

1 - one of the two incidences reported (#EGI2020512) targeted academic data centers "for unknown purposes" (https://csirt.egi.eu/academic-data-centers-abused-for-crypto...) and not necessarily crypto currency mining.

2 - IP addresses associated with that second attack were all assigned to a Chinese University (Shanghai Jiaotong University), CSTNET and one Polish host known to be compromised by someone from China.

Re 2., since when IP is address tracking a reliable method of attack attribution?

It's like trying to assign blame for a terrorist attack based on where the jacket dropped by a terrorist was made. Maybe it was made in their home country. Maybe it was imported. Or maybe they purposefully wore a jacket made in a different country and dropped it on the scene to confuse you.

And in the linked article the probable cause is much more prosaic:

"The attacks may have been perpetrated in order to mine cryptocurrency; investigations are ongoing."

I feel like cryptocurrency miner install is going to end up being the new cover story anytime someone doesn't want to tip their hand on capabilities.

Yes, but if you were serious about espionage, say, you wouldn't draw attention to the compromise by running one.

Unless you're testing a zero day, and staging an alternate route of infiltration to hide your installation of threat persistence.

I believe it's referred to as the "limited hangout" in spycraft jargon. You maintain the target's sense of security and ability to detect intrusion while you maintain the capability to reintrude at will.