The connection between new knowledge and profit is often indirect and cannot be clearly predicted beforehand. And, why must something be profitable in order to justify it? Are there no valid outcomes other than profit?
Because if it isn't profitable then it needs to be subsidized to continue. Given the replication crisis I don't think it's most people's priority to use part of their paycheck for this.
Some of us believe that there are things that are good for society that are worth the money. Medicaid doesn't make a profit. I'm glad people don't die in abject poverty quite as often as they used to.
Why don't people prioritize increasing their income? Like, they could look at wealth inequality and consider that if they owned some of the wealth around them then they could instead generate income from it, which might obviate their desire for lower taxes because they're able to pay their bills with a surplus of savings. What's the purpose of destroying science funding when the problem is a lack of personal wealth?