The plaintiff is arguing that GOOG is guilty of intentional spoliation of evidence, and that execs deliberately moving conversations to ephemeral channels demon

The plaintiff is arguing that GOOG is guilty of intentional spoliation of evidence, and that execs deliberately moving conversations to ephemeral channels demonstrates mens rea; if the judge agrees, they can instruct the jury (or trier of fact) that any missing evidence should be construed through the lens of “adverse inference” — in other words, assume that the missing evidence is, in fact, prejudicial to the defense’s case. This is … not something you want in a litigation, needless to say. So, yeah, you can delete evidence that you know could be relevant to any future litigation, it’s just that if a judge finds out about it you’re going to get hit hard over it.