That's correct, but it's not just "stop paying rent", as that's illegal. In general, a tenant union would either facilitate or assist with helping the tenants set up a rent escrow to be released when the problem is solved and the rent strike ends
What leverage do you have though? You can't go on strike, you're legally obliged to pay the rent you agreed to. You can't withdraw your labour, because you don't do any.
You could work with a court and do something like put it in escrow so the court can see you not paying rent isn't just because you can't. Instead it's about withholding money from landlord to begin negotiations. Basically still acting in good faith but also withholding money to give you leverage. IANAL
Double-check this for your state. For instance, in Ohio if your landlord is not keeping up on their end of maintaining the property you can go to the court and set up an escrow account with them that will hold your rent payments until ALL of the work is completed to YOUR standards, not theirs or the court's, and they are legally barred from taking any action against you for the duration and just about anything they do afterward is immediately suspect of being viewed as "retributive action" which is illegal under the state's renter's rights laws. Always read your rights for your state.