Try not removing context and thinking before reacting.

>Eat good and healthy food, NOT SUPPLEMENTS

Now think about this for a moment. Do a search for "foods high in magnesium," think some more on it. Then ask yourself what would be the healthier way to increase your magnesium intake, replacing some of your diet with those foods or taking a pill?

Excellent. Exactly what quantity of exactly what things?

unprocessed, "natural" food: fruits, all vegetables, raw, fermented, lemoned (potatoes are the food with highest satiety index https://pubmed.ncbi.nlm.nih.gov/7498104/), seeds (rice, quinoa, all kind of peas, etc..), some animal food (eggs, fish, meat). Favor local food and try to balance the food over a week

Excellent. Exactly what quantity of exactly what things?

Pest

It's hypocritical and silly to say "people can just figure it out...wait...no, not like that" when people turn to metered supplements in an environment where asking about specifics leads immediately to handwaving.