I don’t take screenshots at work to share with any of these people. I take them to share with co-workers for business purposes.
If this is blocked and someone wants to share something with competitors, relatives, or journalists, can’t they just take a picture with their phone or a camera? Then it’s never on equipment the company has control over.
My dad worked at a place that blocked the ability to take screenshots on a company phone. The IT department needed proof he was on a certain release of the OS, and they asked him take a screenshot of his settings. He explained they blocked this feature. They told him to use another phone/camera to take a picture of the screen and send that. He tried to point out how silly it was to lock down screenshots when the work around is so obvious, but that didn’t matter. It was all about the illusion of security, not actually stopping anything.