The purpose of the funds was good. It was supposed to provide an easy mechanism for victims to recover damages that would not be as arduous as traditional litigation. The purpose was to increase public trust in vaccines that are commonly required/pushed by the government. It does perform this for the common or known side effects listed in the compensation table. Although some of the amounts approved as caps may not take into account individual differences, and don't provide great flexibility.

It's extremely difficult if it's a rare issue or if the underlying mechanism is not known. This mechanism part is the real downside. You could be completely healthy, get a shot, and two days later be airlifted to the ICU with a heart issue that has no family history or even an explanation for the cause other than "some people just have this" (no genetics really identified yet either). How can you prove it was the vaccine if they don't know the factors that would normally cause it? There are other reports of the issue in VAERS, the patient is in one of the lowest risk populations for first time presentation, etc. Even if you don't have a conclusive underlying mechanism, there's no opposing theory for the "natural" mechanism that would normally cause it (even stuff like which genes cause it), but the special vaccine court will most likely say 'too bad, it might be a coincidence'. If they do that, this seems contrary to intended purpose of building public trust in vaccines and compensating victims in a less confrontational system. Now you don't fight a company, you have to fight the government.