Stratechery's weekly wrap covers the end of the mainframe and OpenAI's continuing turbulence

Stratechery·medium signal

Ben Thompson's 2026.29 roundup collects the week's analysis on the mainframe era ending, ongoing OpenAI developments, and whether Netflix is washed. The mainframe piece is the substantive one — it argues the last durable enterprise computing lock-in is finally dissolving under AI-era migration economics. Useful as a structural frame for why enterprise buyers are suddenly willing to re-platform.