> Acting in concert means knowing participation in a joint activity or parallel action towards a common goal
Memetic spread is not "acting in concert" in the way I meant it or in the way that OP was demanding. There is no common goal in the kinds of behaviors you're referencing.
> You're talking as though the SVB depositors are some sort of hive mind capable of acting in concert. They're not.
… is patently absurd. Startups and the VC market are all about meme copying, on everything from which front end stack or build system to use to how to write a “regretful” layoff announcement on LinkedIn, to (apparently) management of funds.
The boards are incestuous with respect to the ecosystem, and absolutely capable of acting in concert, as constantly demonstrated.