I disagree. You can pop a manual into neutral and take your foot off the clutch so your foot doesn't get tired. If the stop-start traffic is on a downhill, then you can just let it roll.
On the subject of safety, I think a manual is safer. In an auto, you're more likely to be tempted to get distracted by your phone, GPS, stereo system, etc. especially at an inappropriate time, because you have a free hand. In a manual, you never have a free hand, because you always need to be ready to move it from the wheel to the stick if you have to slow down or speed up. Much less tempting to get distracted.
Plus, you're more in-tune with the car, so you're paying more attention to the drive and handling of your car than you would in an auto.