it depends on how affordable sas can become. technology can propagate well only when it's affordable and abundant to everyone. sas is around for quite sometimes, but only a few use it in consumer space. of course 12Gb/s is an option in terms of speed, but pcie can run at even higher speed than sas (over 2GB/s, with nvme technology). about disadvantages, there might be some. however like any new technologies, they will go away eventually.

as a user, i want to get things that are readily available and most importantly, cheap. i still think the combo of sata ssd as boot/software/game drives and sata hdd as storage is good enough for personal computing in general. with ram-caching on hdd's, i don't feel any slowness in my current setup.
have you tried look-ups with google? some possible reasons reported were acronis background service (uninstall it), or rst driver issue (reinstall it)