The problem is, even if your subjective idea of how Autopilot affects your own driving is correct, it appears not to be the case for a significant subset of Tesla drivers, enough that they've been plowing into emergency vehicles at such an elevated rate as to cause NHTSA to open an investigation.

Also, your subjective impressions may be what they are simply because you have not yet encountered the unlucky set of conditions which would radically change your view, as was surely the case for all the drivers involved in these sorts of incidents.