In a perfect world, perhaps we’d all be comfortable in shoes with a 3mm heel-to-toe drop and be able to make use of the biomechanical efficiency they can provide. But such a world doesn’t exist.
Do you wear ‘normal’ shoes to work and did your parents get you to wear ‘sensible’ shoes when you were young? If so, the chances are you’ve become comfortable with the 12mm drop that conventional shoes provide. So for you to switch to running in shoes with less of a drop involves all sorts of risks. A quick chat with some well-established runners confirmed exactly that; they love the feel such shoes can provide but often struggle with the low ride. Some runners have no problems with low-drop shoes, others (like me) struggle. I can run in them, but only for fast-paced, short efforts.
Heel strikers probably need cushioning, support and perhaps something like 8-10mm of drop. Hoka has shoes with superb cushioning that offer a lower ride (5mm) and they’re easier for many to get used to, confirming – non-scientifically – that we love cushioning.
A recent piece of research I read concluded that either you can get on with low-drop shoes or you can’t – it sounds definitive and in the small straw poll I conducted for this answer, it’s hard to disagree.