Storage controllers are like sound cards and modems
Adaptec is going where sound card and modem manufacturers already went. I remember paying $500 for a SoundBlaster 16 and another $500 for a USRobotics 14.4 modem. In the 90s, that was primo kit, and had the kind of margins that Adaptec needs to stay in business.
Today, an AC97 chip costs a nickel, so every computer has audio and modem capabilities for nearly free. This happened because interfaces converged to a de facto standard and everything was offloaded to the CPU.
The market pressures are identical. The physical interface has been formally standardized as SATA, the logical interface has been standardized as AHCI, and offboard RAID matters less now that ZFS is mature and BTRFS is nearly ready.