Naturally it isn't. But those other countries maintain their roads, schools etc. etc. without taxing non-residents on their financial affairs in other countries. The main point is the difference between how the US handles the tax issue vs. almost all other countries.

Now you mention it, renouncing citizenship seems relatively costly compared to e.g. the UK, though I have no idea what the average cost is for renunciation. Perhaps the UK is abnormally cheap! (EDIT: Should probably have pointed out that it's currently £144, or about $215.)

It would seem a shame if people felt they needed to renounce citizenship to avoid hassle/tax. Of course, some may argue that if they want to renounce at all, then perhaps they're not committed enough anyway, but I wouldn't argue that.

It actually costs a great deal more than that. You have to pay 5 years of expected future taxes upfront, in addition to the processing fees. This can be an enormous sum, depending on your income sources. If you just have a regular job and no investments, it is easily more than a whole year's salary. It is insane. In Norway, you generally have to renounce your prior citizenship to get Norwegian citizenship, but they consider it such a financial burden here to renounce US citizenship that they sometimes let you keep it (varies by individual situation).

Not all of it what?

Canadians are not taxed abroad and they have better healthcare than the US. Same with Germany

No question that the USA has a lot of opportunities, but one thing they are #1 is sense of self-importance.