Bull****. Recently I compared a shot with my g4 against my old NEXUS 5 (you read that right). Both in auto hdr. For the g4, the tap to focus made zero difference. The nexus 5 shot was better exposed, and was the overall better image.
From this, I'm going to have to assume one of two things. Either you prefer under exposed images like in your first sample shot, or you have a defect preventing the G4 from metering right.
If you like the under exposed look better for the clouds, that's simply personal preference and I can see where the G4 would disappoint when using auto mode. If you switch to manual mode (I almost always shoot in this mode, as you can still turn off AE-L for it to auto expose), you'd be able to create the same look as the N6 by reducing the shutter speed and/or ISO. I'd probably opt for exposing somewhere in between for better balance and more flexibility in editing. I'd also shoot it in RAW so there's more image detail to work with when editing.
When getting more serious in photography, almost every image will require some sort of editing. Sure, you want to get it as close as possible straight out of the camera so there's less editing to do, but it still happens. Heck, go look through the G4 photos thread here and see just how many great shots have a notation about which editing app they used. Beginners and amateurs may not have a desire to edit their photos, but you need to understand it's all part of the process. If your only desire is to point and shoot, then you need to lower your expectations and understand the limitations you're working with.
If you're tapping different areas in auto mode and it's truly not making a difference on how it's exposed, then you have a real issue. You can test this by switching to manual mode and checking the shutter speed and ISO readings at the top of the screen. With AE-L turned off and not moving the phone, touching different areas should not only change the live preview, but also show exactly how the shutter and ISO are being changed.