The people who have made a science of growing (medical) marijuana indoors, know that there are two requirements for growing (beneficial) light — range (spectrum) and intensity (power).
Usually what is referred to as “artificial” light, is Edison's original incandescent light or the original fluorescents — which if they tried to grow plants, would fail to do so either — because they lack the necessary spectrum and power. So to compare that light with sunlight, is not an equivalent — but if they start talking about halides and the latest state of the art lighting, then it approximates natural (sun)light, including those tanning bulbs — that cause tanning, while you can lie naked under a regular lightbulb all your life and not get any tanning effect.
And particularly important is that range and intensity of light to health and growth of the eye and brain — despite optometrists (eye doctors) saying light doesn't matter. That is what you're seeing — some people more sensitive to these differences than others, just as some people can hear ranges of sound beyond what others can, or sense anything else (taste, smell, touch).
There's a tendency among the social scientists (the politically correct) to make an equivalency of everything — so that no distinctions (and discrimination) of anything anymore, is possible.
In many cases, a person just needs to optimize the lighting, not to need glasses — as often is the case when one uses an Ott light. Another alternative technology that works is the use of a pin-hole (reading glass) instead of
the polished optical glass — that many find helpful staring at computer screens all day, in reducing eye strain. Again, many optometrists (eye doctors) insist that it's not possible or doesn't make a difference when even they use a pinhole instrument to first detect whether one’s vision problem is refractive or eye disease of greater seriousness.
Other vision experts have claimed that they can correct vision defects with the proper training in how to see correctly — because all of our organs don't come with instruction manuals on how to use them properly, correctly and optimally, as most people have to discover on their own — or not.
That is often the case with one’s muscular development, as well as mental development, social, psychological, moral, spiritual, etc. Most often, we learn from those around us — but whole social strata (ghettoes) can often be dysfunctional in that way. That is a common cause of behavioral problems like obesity, addictions, codependencies and mental health issues.