That one is really inexcusable. It'd be better if she had asked Rachel to move the body, so she wouldn't contaminate the evidence that might still be on Mags or something, since X-Factor is the official group who is investigating. And even that would be a bit of a stretch and it would serve only for bureaucratic purposes of keeping the investigation as pristine as possible.
Jean is a very polarizing character, surrounded by many untruthful echo chambers about every aspect of hers. On top of that, some writers/editors really despise her. That's really it.
She's not the only character who suffers from it. But she's certainly one of the favourite targets.
And yes: I'm old. I remember very well what those 15+ years were like.