From what I understand , the vaccine is designed to specifically protect the lungs. So when vaccinated people do get sick, it will feel a lot like a bad cold or the flu, but it will not land them in the hospital.
As far as proof, all I can say is that I have heard doctor after doctor in hospitals/ICUs across the country saying, "Nobody in this ICU got the Covid vaccine. If they had, they wouldn't be here." I don't think anyone is saying you don't get sick with Covid after you're vaccinated (which IS a common misconception) just that you won't be so sick you'll be taking up an ICU bed and adding to the strain on the healthcare system, which is my main concern.
This is not to negate your personal experience- what you're saying makes a lot of sense- but just wanted to add some additional information based on what I've read and seen.
Thanks for sharing your perspective.