Technically, yes. Commercially, no. How would you feel as the buyer of a product if the manufacturer says "but in order for it to work, our approach requires you to subscribe to certain services with the telephone company"?
I totally agree with you that line reversal (or SMET) are more elegant than cadence detection, but cadence detection will also make the product work, and it doesn't impose on the customer.
Besides, I don't know if line reversal is something that you can ask for with the phone company. I know we have it here (Netherlands), but as soon as you are behind a PABX, line reversal is gone. I had to abandon reversal detection on a project once because of this...