I said allegedly because there have been scandals where non-recorded lines were actually recorded and entire cases had to be thrown out because of police misconduct. This can happen by mistake - like if someone at the jail does not realize it is an attorney calling - or maliciously because the jail doesn't care about inmate rights.
So there are just practical "tips" defense lawyers try to follow to minimize the risks to clients. Where I practice, you can call the local jails or state prison and let them know up front that you are an attorney, provide your attorney registration, and essentially pre-register your phone number so they know you are an attorney when you call to speak to your client. You have to tell your client to be very clear that they want to call their ATTORNEY when they arrange to call out. And you just generally would tell your client to be cautious because if he's on the phone yelling how he's guilty, maybe another inmate might hear or a guard. You just want to take steps to preserve your client's rights.
In terms of meeting rooms, I've never personally heard about an attorney conducting a client interview in a taped room. It would be a serious violation of the defendant's right to counsel similar to the drug lab crisis in MA that resulted in many convictions being thrown out.