The only "unearned" income I can think of is inheritance. Which absolutely should be taxed.
I strongly disagree, and rather a high inheritance tax destroys incentive, instead of creating it. This is because of one simple reason: why should a man work to better the future life of his children if the robber baron called the government is just going to take it away. A high inheritance tax would destroy the American society, because rather than the save the money, Americans would spend it in various decadents. Property would be seized. Educational funds confiscated. Savings and equities squandered. In a free society, there is no inheritance tax, on anybody, regardless of the jealousies of the snobbish intellectual bureaucrats, who rob the top workers and wealth creators, investors and business owners, of their well deserved earnings. Anyone who advocates such drivel as the inheritance tax is being played as useful idiots, played so that the robber barons called the government bureaucrats can steal the wealth of the top businessmen to the benefit of their consolidation of power and apparent annulment of freedoms.
Should just note that I don't live in America.
My first and last interest with social policy is equality of opportunity, not the virtues of various parties. A good friend of mine has a similar opinion to you- an intelligent guy, but fundamentally this is the only time I actually advocate for any sort of social engineering whatsoever. Inheritance is the epitomy of unearned income- the last vestiges of an aristocratic, classist society which I personally would like to see gone. To me, a small lost incentive is acceptable.
Someone's life should not, in my opinion, be bettered by the luck of good parents. Every person in society should be able to say- I earned my status. We constantly hear people on the far-left complain about privilege, class and neo-feudalism. Getting rid of inheritance renders those arguments hollow. Until then, they have some merit.
I do not consider the wishes of the dead relevant to the living. Inheritance isn't a freedom, it's a privilege. Again, really is my opinion.
Inheritance taxes aren't a hill I'd die on, but they are definitely something I support. But social engineering is really low on my list of priorities- many things come before it.
I won't engage further here, though, we're both making appeals to emotion and axioms, and we're not going to be convinced by one another.
https://www.prosper.org.au/georgist-glossary/
Rent Seeking
The process of wealth accrual without any productive output. This results from lobbying for monopoly powers via insider contacts. Rent seeking results in poor resource allocation, lower economic output, lower government revenues, increased inequality, higher cost-of-business and national decline. Adam Smith called rent seekers ‘the public enemy’.
Unearned Income
The ability to earn income above the margin of production. Investments in real estate are most pertinent, with the supply of land provided as a gift of nature. The cost of production is zero. As houses depreciate and purchasers compete for ‘location, location’, land price increases have been deemed unearned incomes since the Classical Economics era.
Property Rights
Private property is sacrosanct. However a clear distinction must be made between that which is man made and that which was a gift to all living beings. Georgists believe land should be leased to the state in recognition that no human produced the land, the earth. The improvements (the house) are to be privately owned. Both the lease and improvements can be sold at auction.
So, pigovian taxes, stronger competition laws? I can get behind that- don't think it'd be very easy to actually *tax* economic profit, though.