Having had a really bad post-Covid attack which put me under intensive care only a few weeks after my third jab I've lost all faith in vaccination and won't be having any more unless the powers-that-be make it mandatory.
I can understand how your experience may have cast doubts as to the efficacy of the vaccinations, but one of the great imponderables is what might have happened if you hadn't had the prior vaccinations. You might not have been around to tell us....
Right from the outset none of the vaccines could guarantee to prevent you from catching Covid, nor could they guarantee it would reduce the severity of the infection in every case, but the testing, and now the historical data show that they did make a significant impact in both rate of infection and the severity of infections in the population.
As we learn and understand more about Covid, the vaccines will improve and provide better cover for all. Rather like the flu vaccines, I suspect the covid vaccine boosters will need to be tailored to deal with new variants - such is the nature of Viral infections.