There was a time when it came to 64 bit support Alpha really was the only game in town where you could buy a server without adding a sixth zero to the bill. It was AMD, not Itanium that killed Alpha.
I remember that time being before 64-bit became a requirement for most people (I worked with some computational scientists who did buy Alphas for that reason since they needed the flat memory space without remapping hacks). The Alpha was indeed great but Intel did enough of a job convincing most manufacturers that the only future was Itanium that only a few niche workstation manufacturers picked up the Alpha, and they had 64-bit competition from SPARC, MIPS, and POWER pretty quickly.
I do agree that it was AMD which really made 64-bit mainstream. There’s an interesting what-if game about how the 90s might’ve gone if Intel’s marketing had been less successful or if Rick Belluzo hadn’t bought into it since he killed PA-RISC and HPUX before moving to SGI where he killed both MIPS and Irix and gave the high-end graphics business to nVidia.
HP owned Compaq already, which had previously bought DEC, when the Alpha was killed. HP chose Itanium for their servers. They settled some patent issues with Intel partly by killing Alpha instead of a more traditional cross-licensing agreement.
AMD killed Itanium. HP was pretty far along killing Alpha all on their own.
