"Lightroom exports of 50 photos and Photoshop merges aren't the actual real world?"
I'll let someone else answer you who already did:
"The video tells me two things; that the very real world task of exporting
fifty 40 megapixel images (Ah yes, the ol’ export fifty 40 megapixel images) is slower on the new machine, and that merging some images in Photoshop was around 30% slower, but still incredibly fast"
"As for being advertised for its performance:
MacBook Air is strikingly thin and brings exceptional speed and power efficiency within its durable all‑aluminum enclosure."
To make this stick as a criticism, it would have to be SLOW. And it would have to be noticably SLOW all the time.
Be honest: do you think the base model is ACTUALLY SLOW? For the user?
I think you know the answer.