In-memory computation was already possible with regular DRAM: https://news.ycombinator.com/item?id=22712811

Add a new set of CPU instructions like “rep macb”

...and it's been long enough now, that I can say there was an effort to implement this on standard x86 memory controllers and have the existing string instructions do so, back in the days of SDR SDRAM, but the tradeoffs weren't (yet) in favour.