Then again, DSC could be the one time when it is actually prominent, as the Klingon war clearly is a deviation from the norm for the Federation.
Back in "Context is for Kings" when the black badges were spotted aboard the ship, there was no spore drive yet. There was just this harebrained experiment Stamets was fumbling with. But Saru told the ship was exceptionally configured for running a great many experiments in parallel. SF Intel and its S31 would have an interest in keeping secret the one experiment that succeeds - and this would mean keeping it secret from the other researchers, too. Once Stamets got the spore drive working, and the other researchers got the boot, there'd be no practical relevance to having guards aboard, as the ship would become its own partitioned-off "safe room" for keeping the one secret.
Which would work nicely with Burnham being in the know (there more or less from the start), and Tyler not (he arrives in "Choose Your Pain" where the ship's crew supposedly is pared down to 130-something and the ship has a track record of using the drive operationally in the war).
I don't find the "overuse" of this plot element annoying. DSC is about season-long plots where elements stay on the foreground for fifteen episodes or so. But S2 could already be where the story on S31 concludes, one way or another... Although I wouldn't mind if it only disappeared at the end of S3 or perhaps reappeared in S5.
Timo Saloniemi