Well, according to some IA-64 was a planned flop with the whole purpose of undermining HP's supercomputer division.

Nah, HP made bank on their superdome computers even though they had very few clients. People paid through the nose for those. I worked on IA-64 stuff in 2011, long after I thought it was dead :D.

The real thing that killed the division is Oracle announcing that they would no longer support IA-64. It just so happened that like 90% of the clients using Itanium were using it for oracle DBs.

But by that point HP was already trying to get people to transition to more traditional x86 servers that they were selling.