This is somewhat related to the question, Why can't the homunculi perform Alchemy?

Alchemy is an essential part of life in the series, where not only have the State Military weaponized it, but seems to be at the center of religion and priesthood of neighbouring countries. And yet, only a handful of people practice it. If it's so essential, why can't everyone work with it? We are not experts at all the fields we use, but we use them in some limited capacity anyway. For example, we are not all doctors, but when we have fever, we pop antipyretics; we are not all computer scientists, but we can use computers in our own ways, and so on. In the FMA-universe, alchemy seems to practised by just experts.

We already know that sin-essenced homunculi can't perform alchemy, but Father is a Homunculus (the original one), and yet he can perform alchemy. Ordinary doctors (eg. the Rockbells) have the smarts for advanced study, but don't seem to use any alchemy. Skilled automail mechanics have specialized technical knowledge, but none of them use alchemy.

There are exceptional circumstances where Father blocks tectonic alchemy for everyone, or Edward giving away his portal. But why can't everyone else perform some simple alchemy? Is there an explanation for this in the manga, that is similar to Star Wars' "midi-chlorians"?