The practical history of flash memory dates back to 1997 with the introduction of MMC by Sandisk.
I don't blame anyone for not knowing about Toshiba because they actively detested the technology and shunned its inventor and employee Fujio Masuoka.[1][2]
[2]: "Toshiba gave Masuoka a few hundred dollar bonus for the invention, and later tried to demote him. But it was American company Intel which made billions of dollars in sales on related technology. Toshiba press department told Forbes that it was Intel that invented flash memory."