A coworker interviewing for FAANG got their python data manipulation round ended in 5 mins because he said

A coworker just told me a bizarre interview story and I desperately need a sanity check from EM and ICs at FAANG and top-tier product companies.

He claims he just failed a loop at a FAANG because the interview was strictly rubric-based and the interviewer told him only Pandas is allowed for the data manipulation sections. He told the interviewer he could easily solve the problems in SQL or Polars, but wasn't fresh on Pandas' messy syntax and indexing logic. Apparently, the interviewer just ended the meeting on the spot.

Here is the catch: Only two of us on our team use Polars heavily, and I’m known as the go-to Polars expert here. We have a massive, toxic workplace cold war going on right now. Part of me thinks he completely fabricated this entire story just to spite me, rent space in my head, and make me feel insecure about my tech stack. I haven't interviewed in years, so I’m spiraling a bit.

1. EMs/ICs at FAANG & Top Product Orgs: Is this actually real? Are your automated platforms or live interview rubrics strictly banning Polars and forcing Pandas, or did he just get a power-tripping interviewer?

2. Production Stack: For those at top-tier companies, do your internal guidelines strictly enforce Pandas for .py pipelines? I routinely ship Polars/SQL code to my manager at my current job, but now I’m terrified my day-to-day skills are completely unmarketable for my next jump.

Is my coworker playing mind games, or is the tier-1 tech industry actually this rigidly stuck in the past? Let me know.