bankruptcy does not indicate worthlessness. some companies having difficulties paying their obligations file for bankruptcy to hold off creditors until they can reorganize seeking to have certain obligations/debt discharged or reduced. if they can't then they file for liquidation but even then there could be some worth to owners just not very much. if there is worth the IRS would say you are not entitled to any write-off even if it's only $1.
I provide a link to an article about when a stock is worthless. I would say the same applies to the LLC
https://www.journalofaccountancy.com/issues/2013/nov/20138596.html
you'll have to make the determination as to worthlessness on 12/31/2021 (assumed year-end of the LLC). the date of filing for bankruptcy is not controlling and in fact, may not indicate total worthlessness.
