The degree of incompetence needed for SIGINT/ELINT operations to fail to discover such a transceiver for 6+ months strains credibility.
I'm guessing this is a ruse to convince adversaries that the Navy can't detect Starlink transceivers even when they are aboard their own ships. This is much more likely to be disinformation intended to drive adversaries to use Starlink than it is to be a legitimate failure of intelligence gathering.
Ok, so this is a bit different from taping your password to your monitor. Security has a problem with you doing that, but unless they come to your workstation, they have no way of knowing that you do this.
ELINT is kinda like a security camera, but instead of seeing lights, it sees transmitters. You know the frequencies of the communications transmitters on Navy ships, let's say they are analogous to blue lights. You know the frequencies of their radars, let's say they are green. During normal operation, you're expecting to see blue and green "lights" from your ship, and the other ships in your task force.
Starlink does not operate on the same frequencies as comms and radar. The "light" it emits is bright red, kinda like the blinking lights you see on cell towers at night.
So, you're sitting at the security desk, monitoring your camera feeds... And you just don't notice a giant red blinky light, strong enough to be seen from space, on the ship next to you in formation?
You're telling me that this warship never ran any EMCON drills, shutting off all of the "lights" it knows about, and looking to see if any shipboard transmitters remain unsecured?
You're right, I would expect users to bend and break unmonitored security protocols from time to time. I expect them to write down their password. I expect them to share their password, communicating it over insecure networks that aren't monitored by the security department. But operating a Starlink transmitter is basically equivalent to having the Goodyear blimp orbit your office building, projecting your password on its side for everyone to see.
The idea that ELINT operators missed seeing it for this long doesn't seem likely.