Exactly. Gambling in the real world involved friction. That plus a certain social stigma if you gambled outside of “mainstream” casinos.
And this helped weed out all but the most addicted gamblers. Now there is no friction, the platforms are free to create dark patterns to encourage problem gambling, and the vice has zero social cost.
The dark patterns aren't just in online gambling. Nowdays, a lot of brick-and-mortar casinos encourage, or even require, clients to create an account (often framed as a "members club" or "rewards card"), which is used to track the client's activity at the casino and target them with promotions tailored to their behavior. These can be used in some really troubling ways, e.g. by identifying clients who may have a gambling problem and targeting them with promotions to come back to the casino more often, to stay longer, and/or to start placing larger bets.