Cloud mining sites that you call legit may very well be the same scams that you so carelessly put aside, maybe a little less greedy, or a little more insidious and nefarious if you please. Instead of openly stealing all the money of buyers of their alleged mining power, they steal only a small part of investments making it look exactly like you described, i.e. "far from profitable due to the block halving and the constantly increasing difficulty"...
When, in fact, they might be doing basically the same that outright scams do, i.e. steal their clients money
Easy money making opportunity where block halvings offer a major helping hand in allowing them to pay out only half of what they used to pay out.
If you also add the fact that they can raise the maintenance fees at any time, cloud mining, whether legit or not, is one big scam industry.