It's important in the historical context of the Alpha AXP to also remember the DEC PRISM architecture. Canceled in 1988. One of many architectures killed off by DEC.

https://en.wikipedia.org/wiki/DEC_PRISM

Killing Prism sent David Cutler into the arms of Microsoft.

Another dead architecture was Jupiter: https://en.wikipedia.org/wiki/Jupiter_project

Killing Jupiter sent many of DEC's DECsystem-10 customers to IBM.

Years later, they both seem like bad decisions.