That is simply false. Here is the original press release from Pfizer when they received an FDA emergency use authorization. They never claimed any specific level of effectiveness against infection. The actual study end points were varying degrees of symptomatic infection. And it certainly does work for that.

https://www.pfizer.com/news/press-release/press-release-deta...

https://www.nejm.org/doi/full/10.1056/NEJMoa2034577

Unfortunately, some politicians then started making wild claims about infection prevention that weren't backed by actual science.