Let's agree that the government has a legitimate need to regulate this.
Let's assume they set up an organization of 100 people with average salary of $100K per year to regulate and monitor the industry. Seems like plenty to get the job done.
In 10 years they spend $100M in salary. Throw in another $100M for overhead costs. Total: $200M over 10 years.
Remember, industry develops the technology, pays all testing and regulatory costs, etc. Government just works with them to make sensible rules and confirm the rules are followed.
So how do you come up with a proposal for the government to "invest" $4B, twenty times as much? Answer: government overreach.