NASA also had a very large amount of government funding from a cold war effort at the time. A large portion of the military spending was diverted to NASA during that time period.

You saying that SpaceX's biggest win is two starship catches and the Polaris Dawn mission in 20 years is entirely wrong. As I mentioned, the vast majority of their operating time has been spent on making Falcon 9 land and be reusable, not on starship - the number of launches stat is important for that reason because it directly impacts their goal of being rapidly reusable which is something no other rocket is. Starship has only been in testing since 2019, and the booster since 2023, so if you said 2-5 years instead of 20 you'd be closer to correct on that one, but saying 20 when referring to Starship is wrong. If you want to talk about 20 years then you have to include Falcon 9 and the landing systems they've developed that no one else has done yet. Their goal is to be rapidly reusable, and nothing else has come close to being able to launch as often, which is only possible because of their R&D put into the Falcon 9's landing system.

You're also not recognizing that the math and science aren't already worked out for what SpaceX is doing, otherwise they wouldn't have had to spend the R&D time to figure out how to get Falcon 9 to land, and other rockets would have already been landing. Now with Starship they're trying to get the second stage to land as well, and catch the booster. These are entirely new problems to solve - NASA never landed an orbital rocket, caught an orbital rocket, or reused a second stage. New Glenn is also having to solve the landing issue; it's not already worked out, and the math changes considerably depending on the specific vehicle and its setup.

You could say the shuttle was a "reused" second stage, but the sheer amount of refitting that had to be done after every flight was the entire reason the shuttle program was cancelled; it didn't reuse as much of the actual shuttle as it purported to - they essentially had to assemble a whole new one every time Ship of Theseus-style, and all of the heat shield tiles had to be replaced after each landing which was a massive effort since each tile was entirely unique and handmade. It could never have supported anything near a rapid launch cadence that starship is trying to achieve by developing things like a more generalized heat tile design that can interchangeably be used across most of the ship.

I don't like Musk much either, but SpaceX has some real engineering going on, and you're not giving those engineers the credit they deserve for these systems that NASA hasn't done.