It's entirely possible that this aerospike engine is actually lighter because they don't need large nozzles and nozzle extensions and are more efficient
Standard nozzles do not need a cooled support structure right in the middle of the combustion chamber. I love these things, I made a linear aerospike (Never fired), but this thing just looks heavier than a standard TCA/nozzle
It's entirely possible that this aerospike engine is actually lighter because they don't need large nozzles and nozzle extensions and are more efficient