those ceramic hybrid sram things seem to have been very popular, did the sram makers stop making them in pdip or something?
I am not exactly sure that I understand your question.
In any case the Tandy Model200 and 100 were the portable small computers of that day, lcd display, running on AA batteries for what I remember 12 hours or something like that, size did matter. So 8kB pdip srams would occupy too much space.
there just seems to be a lot of ceramic pdip hybrids that have multiple smd srams mounted on them, i have some in my little collection, like the world needed pdip parts but the makers were only producing smd