I think he overemphasised it compared to what other 3e authors wrote though - with, for example, baelnorns and archliches (undead that are neutral or even good, in Monsters of Faerun).
And of course there's Good gods that occasionally create undead, like Tyr, who gave a paladin who'd failed in his duty and died, a second chance by bringing him back as undead.
"It's evil, but not so evil that Good characters' can't do it without changing alignment - minor evil rather than great evil"
would be how I'd judge Tyr's act.
Though another way of looking at it, might be "That paladin is only undead because he's a 2e character. In 3.5e, he'd be a Deathless instead".
Same might apply to archliches or baelnorns. Archliches cannot be turned by Good clerics, and when an Evil cleric attempts to rebuke/command them, they are turned/destroyed instead. Sounds very much like a prototype for the Deathless concept.