Compilers simply could not keep up - that was reality, not just marketing. Ideally, Intel should have coded the compilers too and removed the rough edges. But they were a bit too slow and AMD ate Itanium's target market.
You have to admit though that the EPIC (Explicitly Parallel Instruction Computing) model was quite innovative. The philosophy influenced the LLVM project and some of the principles are used in GPU's and AI accelerator chips, even if hardware-based dynamic scheduling won the game.
