Let the public decide, and you get popular art. Let the rich people decide, and you get whatever art the elites value. And also have some public funding, and you get the kind of art experts and some politicians value.
Let the rich decide by their own preferences. Let the public decide by their own preferences. Take money from the public and give it to politicians and bureaucrats so they can decide for the public. The first two make sense. The last does not.
What do you think about the tax deductibility of charitable donations then? To me, it seems to be the worst of both worlds. You are still using tax money to fund some activity, but instead of having public control with checks and balances, you let rich people decide how the tax money is used.
It can be argued that tax deductions for donations make sense, if the government is already using money for similar purposes. You then get a greater effect from the tax money, at the expense of losing control over it. But if it's not the government's job to support the arts, then all donations to the arts should be made with after-tax money.
But there is an argument that some people are truly experts in art, they have studied it and made it their life's work. That we should allow them to make the decision for us, because they will be able to make better decisions. We do this in a lot of other areas, after all.
Amount of art knowledge isn't subjective, it's a testable and verifiable metric. And the idea that all subjective tastes should be equally valued is a relatively recent invention from within the last generation or so that isn't taken very seriously outside of entry level art appreciation groups.
You can have whatever subjective response to art you'd like, but whether your response should be considered as serious insight and commentary into the structure, context, and significance of that art depends on how much time you've spent studying the field and honing your ability to read artworks.
If the only music someone listens to is top 40, I don't think I care very much what they have to say about Bartok. If the only paintings someone is familiar with are the Mona Lisa and Van Gogh, they're not qualified to speak about an Imhof painting. Someone wearing Walmart doesn't have anything interesting to say about Demna. You get the idea.
I think the common response to this is that it is elitist and exclusionary... But we are elitist and exclusionary in most other fields too. Nobody would listen to the engineering opinions of someone who can't name a programming language. Art is more experiential, sure, but not all experience or cognition that arise from experiences is of equal insight.
And how is that enforced for engineering? The answer is it actually isn't. Anybody is free to build their own product and sell it. And the public chooses to buy only products built by professional engineers because they are better. Why can't we do the same with art? If these "experts" are as good as they say they are, they should be able to win in the free market. We don't need the government to take money from the public to support them.
This is some kind of bizarre reflexive libertarian outburst to my comment that had little to do with the role of government.
Firstly, lots and lots of people use government-engineer built apps. I pay for the products of government engineering contracts every time I tap my phone to enter the subway. Car commuters use it every time their plate is scanned to cross a government-built bridge. Often the same companies that carry out government, tax-payer funded contracts are also taking on contracts in the open market.
Governments fund non-profits like art museums because these institutions, while existing within the free market, provide a public good that most agree ought to be as accessible as possible. To that end, the non-profit model allows for museums to guide themselves based on an ethical mission (usually having to do with providing accessible art and culture) rather than a profit-driven market strategy. They are still private, so the board has autonomy from government oversight, but they have tax structures and funding structures that position them as utilities rather than business ventures.
Museums, like for-profit ventures, still compete for funding, they still compete for relevance and cultural capital, and they are still beholden to providing a service that people care about. Fantasizing about slashing government budgets doesn't really make sense here. The government is taking money from people to fund museums because if we all pay $100 a year to arts funding in our taxes, we get to go see sculptures from 2500 years ago in a palatial building attached to a giant park for free... Without group buy in, that same experience might be stratified to only the very wealthy.
You seem to think it is politicians deciding what art people see. In reality, it is arts experts pitching the relevance of their expertise to secure funding and outputting culturally significant material to justify their existence in the same way software engineers make themselves appealing for government contracts.
Art preference is entirely subjective. They might be experts on describing and knowing about historical art, but they have no more lgegitimacy in their preference than anyone else.
Let the public decide, and you get popular art. Let the rich people decide, and you get whatever art the elites value. And also have some public funding, and you get the kind of art experts and some politicians value.