The best definition I've seen was in a book titled, "Rich Dad, Poor Dad". The author defines wealthy as a condition where the income from your assets completely covers your all your costs of living and basic subsistence. You don't need to work to cover your food, clothing, shelter, utilities, etc. It doesn't necessary mean you are swimming in an ocean of disposable cash. You've simply reached a point of financial equilibrium that doesn't require further income to be stable.
So according to the author of the article and the best definition you've seen as "wealthy" "most saving and investment are done by the wealthy"...BS! How many people/investors fall into that category?