Cost immediately comes to my mind. Given that gigabit service is the gold standard of residential Internet, it is not clear what would be gained for the cost o

Cost immediately comes to my mind. Given that gigabit service is the gold standard of residential Internet, it is not clear what would be gained for the cost of SFP ports and modules. It is also unlikely that we will see residential service reach 10 gigabit speeds, as most consumer devices would never be able to take advantage of such a thing, and even at 10 gigabit it is probably cheaper to build everything as SoC rather than have separate modules. The only reason I can think of to bother with SFP for residential connections would be GPON, but according to a Verizon tech I asked about this it is far cheaper for them to just use their ONT (which also supports their triple play package), and I was the only person he had met that even had a router with an SFP port. Until you are looking at speeds above 10 gigabit or need to run particularly long cables (beyond 100m, which would almost never be relevant to most consumers) there is no particular need for SFP, and the added cost and complexity is beyond what most consumers want to deal with. Given that most consumer devices cannot come close to saturating a 10 gigabit link and people mostly use wireless links anyway, there is no real point in putting SFP ports in consumer devices.