Yea, this is 100% BS. This is two things.
1. An author writing about things he doesn't understand.
2. Insane levels of contrivance.
What happened here would never happen, even in the newest and most basic of start up companies, to the most monolithic and bloated mega corporations. Anyone with the permissions to do what he did would know better, hell, this mistake is something you'd probably figure out not to do in your first week learning SQL. Literally type DELETE and SQL into google, and in every single website that popups it tells you exactly what happens if you leave off your conditions in the first few lines. And any company without any backups, that has or allows developers to write directly to production deserves to fail. Literal highschoolers know better than this.
This is dumb drama for drama's sake, and the author is just hoping people who know better would ignore it. This is like a professional cleaning service mixing bleach and ammonia, or a mechanic somehow magically connecting your exhaust pipe into your air intake or an epileptic firearms instructor handing a loaded, fully automatic gun, safety off, barrel first to a first time, also epileptic shooter, with his finger on the trigger while at a rave. Literally never going to happen in any realistic setting unless it was intentional. Blaming the character seems stupid because of how unrealistic this is. This is foremost stupid writing, followed by insanely incompetent fictional superiors, and then lastly his fault.