He was the first to publish an open way to communicate with him in order to out the corporate crazies, and readers did in droves, explaining the inanity of their workplace and getting secret retribution for stuff they clearly couldn't complain about publicly.
A good percentage of youtubers and substackers today actively cultivate their readership as a source of new material. They're more of a refining prism or filter for an otherwise unstated concerns than a source of wisdom.
Doing this seems to require identifying with your readers and their concerns. That could be disturbing to the author if the tide turns, or to the readers if they find out their role model was gaming them or otherwise unreal, but I imagine it is pretty heady stuff.
I hope he (and anyone facing cancer) has people with whom he can share honestly, and has access to the best health care available.
The comic I remember was overwhelmingly about the banalities of working as a corporate engineering type. One of his peers was black, another was a woman, and they were not the butt of the joke. Pointy hair boss was.
AFAIK, the only non-White recurring Dilbert character was Asok the Intern, who was Indian.
A black character (who Adams himself described as the first black character in Dilbert) did appear in 2022, but, well...
https://www.reddit.com/r/onejoke/comments/ugunog/after_33_ye...
Still. "White guy writing about banal stuff must be white privilege/resentment" is a real stretch to apply to the comic during its prime. Your 2022 example only highlights the contrast.
The closest example I could think of from the 90s was a riff on whether you're supposed to open the door for women or not in these modern times, and it felt much more "confused everyman" rather than "aggrieved partisan".