This is extremely revisionist. Microsoft did a two-tiered badging program for Vista: Vista Capable and Vista Ready. They originally only had a single tier: Vista Ready.
Vista Ready hardware had WDDM drivers, adequate RAM, and capable enough graphics to run Aero. Such hardware could run any version of Vista. Vista Capable badging was introduced later which meant the hardware could only really run Home Basic which didn't support Aero. This badging program was for hardware sold contemporaneously with Vista's lease.
Millions of Vista Capable machines were sold that were honestly barely able to run even the Home Basic version of the OS. OEMs ended up having to offer downgrades to XP because of Vista's performance problems. Out of the box it ran slower than XP on the same exact hardware. Lots of third party software ran slower on Vista vs XP.
Vista was a terrible release of Windows. People that had problems with it weren't just people with old hardware upgrading. If you ran it on a high end system you probably didn't run into many of its performance issues. It basically brute forces it's way to usability. For many millions of others Vista was a shit show.
On the other hand, Vista did provide a mass market platform that could be a great scapegoat for the 64-bit transition. Everyone needed new drivers anyway.
As I recall, the XP-64 product was basically a painted over Windows Server release that was basically a non-starter.