Why is it important for licensed professions to have ethical requirements?

Steven Badger, a carrier$-$oriented attorney, supports a Texas bill that prohibits policyholders from hiring public adjusters through an endorsement in the insurance policy. Most public adjusters' fees are a minimum of $10\%$ of the final settlement. This means that if the net settlement is $$10,000,$ the public adjuster will earn $$1,000.$ It may not seem like a lot, but in the example below if the damage costs $$10,000$ to repair, the insured would only receive $$4,500$ to repair the damage. Granted, if there wasn't a public adjuster the insured would receive $$5,500,$ which is not much more, but the insured knew they would be responsible for the depreciation and the deductible. However, most public adjusters state the insurer never writes all of the damage, and policyholders need them to get what is owed. Therefore, is this prohibition a good idea?

Why or why not?

Is it ethical for public adjusters to be paid as a percentage of the estimated damages?

Why or why not?