In respect of loading, I certainly agree there is room to permit trucks backing out, where this can be done safely (sightlines, road width etc.)
However, it is important to note we certainly don't want trucks backing out to major roads during rush hours or high volume travel times, as this could lead to significant additional congestion, including for transit.
Where the access is limited to side streets I'm inclined to support removing the turnaround requirement, though each street does need to examined based on circumstance. (for instance if the side street features a fire hall or EMS facility in the same block, you want to be careful not to delay response times by 90 seconds or more.
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Worth adding, many of the issues around the turning requirement would be mitigated by reducing the size of waste-hauling trucks. Of course, this would increase the cost of delivering said service (with more trips to transfer stations required); there are always tradeoffs.
