Comment by agentultra

I work in card payments transaction processing and IO dominates. You need to have big models and lots of data to authorize a transaction. And you need that data as fresh as possible and as close to your compute as possible... but you're always dominated by IO. Computing the authorization is super cheap.

Tends to scale vertically rather than horizontally. Give me massive caches and wide registers and I can keep them full. For now though a lot of stuff is run on commodity cloud hardware so... eh.