And what does this say exactly? Bad network affects all phones equally.All those simple tasks depend on speed of internet and signal strength given by particular mobile operator.
Even if the ad shows they are in lift, the building might be having a tower nearby too. Or like all ads, the lift would be fake with a wifi router nearby. Or the sequences might have been sped up a bit to fit in the 10 second ad slot.
If they were in a lift in an area with weak signal could the phone do those tasks as fast as shown in the ad remains to be seen.
And moreover, it's an ad. They could've faked the entire thing for all we know. Almost every ad is faked and doesn't show the real deal.
The point they're making is not the network speed, but how fast you can interact with their UI to perform basic tasks. Taking a photo doesn't use network, nor does opening up offline maps. Those actions can be done real quick in Lumia phones.