Working soon two decades for a serious and legally licensed Casino (not mine) and also playing myself for testing and some fun I really doubt from gambling its impossible to make a steady living, the house edge is always there the house always wins in the long term which is what consistent earnings would be but they simply aren't when it comes to Casino.

I could see an exception as a professional Poker Player whereas i.E for Texas Hold 'em the chances dealt with the Cards (Hands) your gameplay and strategy can favor you its more than a simple calculation like casino games are. I mean it still is but as a Player, you can add flavor, and no you can't do that on Casino games.

I see Sports bets, gambling, and Casinos as forms of entertainment like going to the movies in my case I pay a couple of euros per month to Blizzard Entertainment for their famous MMORPG and there I can't even win any money. I get a chance to win purple Pixel armor after killing a Raid boss but again broken down to what this is its also that's the same sort of entertainment, just with a fixed price.