[DavidNielsen]

I suspect it’s more that Carmack isn’t one to reminisce to the same degree as Romero. Romero clearly makes games because he loves playing them, whereas Carmack does so as a technical challenge. For Romero, Doom is a highlight of his life for emotional reasons, Carmack, on the other hand, mostly seems to view a game being fun as an unnecessary side effect of it being technically impressive.

They are different types of people, and they both are probably adults at this point, at least sufficiently to acknowledge that their common ground is having a beer and discussing cool new stuff once in a while rather than the style of friendship which would involve being willing to take a bullet for one another. If their interests intersect then they can talk and be excited but those points are too fewer to call it a deep friendship. It is mutual appreciation of technology and cool stuff.

I would not read into it that they are unfriendly though, just that the type of friendship is bounded by interests and passions and I doubt either one has hard feelings about the past.