Say someone silly makes a rule that your need X hours of training annually to be an interior decorator. Now besides the training, you also have to know that that's required, you have to maintain records to prove you've had the training, the government needs a process for verifying that you've had the training, ...
If correct/moral/societally beneficial behavior was the most profitable then no regulation would be needed.
Lacking regulation also has a cost, it's just not to the unregulated. Dumping waste into a river is cheap for the business doing the dumping, but has environmental impacts on everyone downstream. It's more expensive to properly dispose of or recycle waste material, that's why a regulation that you must do that is needed.
The market simply does not hold bad actors accountable in any meaningful way. As a result, it pays to be a bad actor.
It's simply not a black and white issue. There are bad regulations to be sure. But it's not nearly as simple as saying that less regulation is better or that more regulation is better. The right amount is good and the wrong amount is bad. What that amount is is up for debate.
This applies also to enacting monstrously stupid regulations. Or even ones that were introduced entirely as revenge or to create opportunity for corruption.
That all sounds good, we just need to make sure "X" is reasonable. Having reassurance that any licensed decorator had an amount of training/testing is good for the customer.
Unfortunately your silly rule is something that exists (not for interior decorators of course) but for countless other trade jobs (barber, plumber, etc). Whether that's good or bad I can't say
I personally see it as good. Why wouldn't I want someone I trust with my hair or pipes to not have something to vouch for them?
It's only a downside if you see cost as the most important thing about all else. The clear consequence is that a trained barber/plumber will require higher compensation to make up for the training, and due to less supply since not everyone will be able to get a license.
It's unambiguously good, and that's coming from the perspective of someone who is routinely frustrated by regulations around residential plumbing and electrical work. It would be utterly insane to remove minimum credential and testing requirements from trades where fucking up results in catastrophic damage to a structure, fires, etc.
Say someone silly makes a rule that your need X hours of training annually to be an interior decorator. Now besides the training, you also have to know that that's required, you have to maintain records to prove you've had the training, the government needs a process for verifying that you've had the training, ...