Ted, it is very solidly progressive. As different people will tell you, they can go a good long time between visits to a cardiologist or back to an EP. Over on afibbers.org, the admin there had five ablations between three different EPs until he finally found out about Dr. Andrea Natale in Austin. He is now almost eight years AF-free. Previously, he was back in AF within a few months to a year. Other frequent posters there have gone several years, but they've all agreed that eventually they had to undergo yet another ablation because they began to get fibrillation again. It is an incurable disorder/disease (it is called both), but like some other conditions, it can be controlled well with proper care from a care provider and the patient, him/herself.

This site says, "...almost always progressive..." https://www.webmd.com/heart-disease/atrial-fibrillation/afib-gets-worse
This citation says '..chronic and progressive...' : https://pubmed.ncbi.nlm.nih.gov/33516398/
Scroll about 1/3 of the way down this page to where in bold it asks about AF going away:
https://drafib.com/blog/what-is-paroxysmal-atrial-fibrillation
Yet another 'almost always': https://health.clevelandclinic.org/atrial-fibrillation-dispelling-6-myths/

It is always the case that there are 'outliers' who beat the odds. Perhaps one out of 10-to-15 persons diagnosed with AF will need little or no treatment over many years. But the very heavy majority will need it strictly managed, and even then there will come a day when things change and they'll need another tool in their pocket to deal with it.