Canada is the only place that consumes 18.5" rifle. Only things from the 70's have long rod because back then everyone still thought a rifle needs to be 18 to 20 bbl. All those rifles back in the days use the gas block to retain handguard, so there is no choice but to make a long push rod .
Mechanically the shorter the rod the less can go wrong ( look at G36 and how they made the first retained pin hanguard that can be taken off to service the gas system, once the gas block is not used to retain handguard, they optimize the push rod length) - the rod itself and also the angular alignment. With short push rod, the handguard must be able to come off easy. So either path A or B, the compromise needs to be made.
But this is also the consumer market. Aesthetic, pre-conception ( like this over-gassing idea)..are just as important. Like the side charging handle business, IMHIO it is the weakest point of all the Canadian rifles.