You could definitely buy major name consumer grade 286 desktop PCs in 1990.
My dad replaced our family's z80-based Heathkit with a 286-based Packard Bell on or around that year.
A lot of people just didn't use Windows back then, and the extra cost of a 386 had little advantage if you weren't doing gui+multitasking.
It wasn't the 386 that ushered in the end of 16 bit computing, it was windows 3.1... which could run on a 286 but was painfully restricted there.