There was plenty of evidence that Jan was a sociopath, or Ryan (obviously), but David had quite literally 0 sociopathic tendencies. Plus, this author said something about how David (and Jan) were both 'clueless' about Michael's incompetence, so it isn't like you can argue that David knew he was incompetent but tried to get him promoted to corporate anyway (which would obviously have been manipulative, although that alone wouldn't make him a sociopath).

When Dwight did random crazy shit, like set a fire in the office to do fire safety awareness day, David told him straight up that he couldn't do that and why. At no time did David display a lack of social skills, lack of empathy, or antisocial behaviour (except for a bit after he gets fired and prior to starting up Suck It). The most you could probably say there is that when Michael and Holly were forced apart (Holly back to Nashua), David was a bit muted - but even then, he tried to send Michael on a vacation (which got Michael laid in the end), even though the episode ends with Michael raging at David.

I'm happy to hear what the 'plenty of evidence' is.