That is a vast overstatement.

Many card issuers such as Amex in the US and several of the large banks are processing properly documented chargebacks in very short order. If the ticket is covered by something clearcut such as US DOT rules or EC 261/2004, a temporary credit is issued within a day or two and a permanent one issued in fairly short order.

Chargebacks should follow the letter of the requirements and should be, if possible properly documented with a copy of the e-ticket receipt, the cancellation notice (or other evidence of carrier cancellation), the passenger's request for a refund to the original form of payment and either the carrier's refusal or non-response. If you can't upload documents, provide a summary in the chargeback.

Keep screen shots or copies of everything. It may seem faster to do things on the phone, but it is sometimes worth a day to get things straight.

If you bank is foot-dragging, remember that. This may not be the time to switch banks, but when things calm down, it's worth asking around with your colleagues and friends about which banks were supportive and which were not.