Cause SIPR, JWICS, GIANT etc… are nearly impossible to access - to the extent where for SCI info (which is arguably the level of data they were passing) they constrain you to having to communicate in a certified SCIF
The SecDef has a bunch of SCIFs but even NSC staff don’t to the same degree.
People pass TS/SCI data outside of the system regularly - congress is notorious for this and I have personally had multi year operations shut down because a congressman talked about it at a hearing.
I know of plenty of parking lot “SCIF” and sneakernet SCI conversations because time was an issue
The reality is this admin doesn’t care about the structures that the national security community is statuatorily mandated to use, but there’s nobody that is going to do anything to them about deviating.
Classified networks suck to use, anyone who can get around it does. The fact that its the secdef and nsc and they got busted just demonstrates that they view their behavior as more important than the system.
Left to the viewer to determine if thats a good tradoff