A single prisoner dying in a remaining camp now being used as a prison in 2024 is a far cry from making the argument that "gulags were essential to the Soviet system."
The argument that gulags were essential is "when their use was drastically reduced, the Soviet Union declined". I think that's overly focused on one element - the collapse had many causes - but easing up on dissidents is likely to have played at least a part. I'm not surprised today's neo-Stalinists yearn for a return to the system.