Russia is no longer a superpower. With the 9th largest economy and population that is to be expected. The only way it can compete is by using its military. The issue here is that it did inherit the Soviet Unions fairly capable military, but due to not having the same resources as the Soviet Union(it lost like half the population and a good chunk of its economy when it broke up), it was unable to maintain that. So a huge part of the number of tanks, planes and so forth Russia had on paper, just did not work properly. So when they invaded they were unable to win.

Iran and the US are a different story. The US was clearly capable of basically destroying the Iranian air force and navy with relative ease. The main issue is that it does not take much to close a strait. We have seen that with the Houthis and the Bab El Mandeb earlier. Basically the only way to deal with that is to invade Iran and everybody knows this will be very bloody. The US could probably do that, but chooses not to.

Generally speaking a superpower is a country, which position is considered by all other countries when making important decisions. This does not mean that they do what they want, but they certainly think about it. Currently that is the case for the US and China. I doubt this is going to change for the US here. They have clearly shown to be able to cause some serious damage against Iran, which is on the other site of the globe for them.

A Great Power is a country, which can influence decisions all over the world, if they want to. Currently that is probably France, UK and Russia with India, Germany and Japan being somewhat close as well.

Although the war is seriously hurting the Russian ability to project power abroad. They were unable to seriously support Venezuela and Iran, when they needed help. Sure they seem to supply some inteligence to Iran, but without the war against Ukraine, they could have delivered weapons. In the case of Venezuela that happened a bit, but it was token support. They also lost Wagner and seem to have issues with their power projection in Africa due to that. A big part of that is that the long range aviation has been hit hard by Ukraine. Also the navy has a lack of large new warships like destroyers. Their weapon sales are also down. It would take a long time to rebuilt that and it is entirly possible, that they end up not being even a great power after this.

If Ukraine wins the war, then the Russian economy will be in decline as war spending is already falling and their exports are mostly fossil fuels, which have been hit by Ukrainian drones. They also would lose millions living in the land they took from Ukraine and the economic decline will be accelerated by Central Asian migrants not coming as oppurtunites at home or in other countries are just better. That also makes rebuilding their military much much harder. Especially global power projection is very expensive after all.