A proposal to scrap federal income tax for workers under 30 on their first $500,000 of earnings would be good news for young workers but would cut government tax revenue.

• Under the idea, anyone under 30 would keep every dollar they earn up to $500,000, paying tax only on income above that line.
• The reasoning comes from business: if the deal is no longer good for the newest person joining, the whole business is in trouble.
• Young people today lack the same shot at building wealth that earlier generations had.
• Letting them keep more money is meant to push more marriage, more kids, and more first-time home buying, all of which are lagging.

Outlook: This is an idea rather than a policy in motion, with no sign of it being taken up in Washington soon.