Bill, The economists argue about who gets to impose the taxes and on what. There are many conflicting opinions and practices.
Usually, it is only the governments that own the territory of the activity that can levy taxes. However, the U.S. levies taxes on its citizens no matter where they live and work - which actually results in about 3,000 U.S. citizens per year who live and work in other countries deciding to renounce their U.S. citizenship, even though it has an associated fee of $2,350.00. Within the U.S., various states have various taxes on residency, property, often including inventories of businesses, taxes on paychecks, and most have taxes on sales. That can lead to people paying a lot of taxes if they work in one jurisdiction and live in another jurisdiction. There is a lot of hypocrisy involved in the supporting logic. For instance, Washington DC, the capital city of the United States, was specifically established to be a non-political locality that is not in any state. So, people living there do not have representatives in Congress, but they still pay taxes to both the District and national governments. They want to become a state, and argue that they are being taxed but not allowed representation in how that tax money is used. Hypocritically, they simultaneously want to tax people who work in DC but do not live there, and do not want to let those taxed non-residents vote in DC elections to say how those tax proceeds will be used. However, there are many in DC that want to let non-citizens of the United States who live in DC vote in DC elections.
The obvious conclusion is that governments need and want more money, and adopt whatever taxation philosophy will get them more. There is a lot of disagreement on what is "fair" to the people being taxed. On top of that comes the arguments about how the proceeds from those taxes get used and whether that is "equitable".
Going to how that is all going to be reflected in making the "resources in space" get "distributed equitably" to all the residents of Earth seems to indicate much potential for disagreement. For example, some are worried that China wants to "claim the Moon" based on establishing the "first permanent residence" there. China seems to be pursuing a similar policy in the South China Sea, building islands on shallow areas and claiming sovereignty in the surrounding sea areas. Others want some sort of universal ownership similar to what has been negotiated for Antarctica. But, Antarctica is not currently used for resource extraction, so that doesn't really establish a precedent. The current scramble for resources in the Arctic Ocean as it becomes ice-free seems like a more likely scenario to play out in space.
And, even if the U.N. can decide on a tax on space profits or space inventory, it really does not have the means to enforce that, any more than it can enforce all of those resolutions regarding nations like North Korea and Iran and Israel, etc.
So, I don't see any real chance for changes in the status quo regarding "fairness" and "equitable" in space. The entities that can make a profit will do so, and others that cannot make a profit will fail and not be extracting resources from space. Governments can really only decide how much of the profits they can syphon off the processes before they become unprofitable failures. It is in each of the governments' best interests to not force everything within their jurisdiction to failure, because then that government gets nothing - some other government gets it, instead.
That is how it really works, and sometimes fails to work well, because different economists have different predictions about the effects of various policies, and they are often very wrong in predicting the future effects of their policies.