If you read the link, read the article, clicked on the link that it shows as the source, you get this headline :
Russian Cosmonaut Allegedly Photographed Confidential SpaceX Docs, Removed From NASA Crew-12 Mission
And if you clicked the link on that, to the russia source, google translate states the following :
Headline :
Cosmonaut Artemyev was expelled from the crew of the Crew-12. He photographed SpaceX documents and “brought out in the phone” classified information – sources
And part of the article :
Trishkin’s sources said that Artemyev was expelled for violating the export restrictions of ITAR: the astronaut allegedly photographed the documentation of SpaceX, and then “brought secret information on the phone”. In an interview with The Insider, the expert said that an interdepartmental investigation was launched:
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So, it does seem he had access to documentation that he should not have seen at all. It's not taking some pics of just the ship / flight controls, etc.