I think there has to be more to the story here to be perfectly honest. People have been chopping chrome lined barrels since there have been chrome lined barrels to chop. There is nothing special about the SCAR barrel except that it is a hammer forged tube with the extra thick 249/240 lining. At the very least the guy could have had the crown touched up a thou or two and tried again. Also, reading his post he simply removed the gas port plug in the gas block instead of resizing it. He may have severely overgassed his gun. While that shouldn’t effect the crown it tells me that he may have taken short cuts elsewhere.
Mine is off being chopped right now by a reputable smith that has cut hundreds if not thousands of chrome lined barrels. I’ll keep the collective updated as to how it performs, but I don’t foresee any issues.