I call shenanigans. There is a bar code on the bottom part of the postcard. It has 65 bars. This is consistent with the Intelligent Mail Barcode that was introduced in 2013. Prior to that there were different barcode standards, Postnet and Planet, but neither had 65 bars, the highest number of bars that Postnet had was 62, and they were short and long only. This barcode here has 4 types of bars: short, long up, long…
It is far from inconceivable for a postcard to be lost in USPS-land and then years-later complete its journey, getting a bar code affixed. This would not be the first time this has happened. Other times, entire bags of sorted mail were lost and recovered decades later and then delivered.