Ventajas
The ground-floor employees are genuinely great people across all the depts. There's a strong sense of cameraderie in all the misery, despite the management pathetically trying to introduce sad little incentives for a rat race. Developers and other technical personnel are very knowledgeable, at least those that remain in the company. There's a lot you can learn from your senior colleagues, and many of them are happy to share. Also, no 'return to office' mandate so far, so good.
Desventajas
Worst management you could possibly dream of, not merely incompetent, but a band of nepotistic Brits with severe class neurosis, who treat the ground-floor employees like indentured servants whose job is to worship the ground their bosses walk on. Any disagreement, even most courteous, wounds the bloated C-level egos like shrapnel, and gets you booted out of the company, no matter how quality your work is. I have witnessed instances of mobbing that were actually straight up legally actionable, this company is very lucky the victims typically prefer to just switch jobs rather than deal with the hassle, or with raising it with the powerless, purely-decorative HR dept. On-call/off-call is not respected at all, and neither is labour law. In a financially rough situation that the company happens to be in, the leadership's priority is not taking care of the employees that actually build and maintain the product they're selling, but rather hiring new C-level colleagues at premium and simultaneously offending the ground-floor with ridiculous, way below market rate wages.