It reduces your risk of infection taking hold, rather than being cleared fast by exposure to the pre-primed immune response ready and waiting.

macroscopically that can look like prevention of infection.

Increasingly nominally. Right now, the protection is about 50%. I expect it will continue to fall as the virus evolves.

50% is a lot from a public health perspective -- there's a huge difference in the exponent -- but not something you can rely on to keep yourself or your relatives safe.

So what you’re saying is: it reduces your risk of infection? :)

I agree that it’s waning, and likely boosters will help, but it is far better (and safer) than doing nothing; just doesn’t preclude the need to mask up around unvaxed folks, etc.

It doesn't preclude the need to mask up around vaxed folks either. Delta is spreading in part because vaxed folks stopped taking precautions, trusting in vaccines. That's not good for anyone. Vaxed folks won't get severe cases, but the jury is still out on long COVID. It also applies strong evolutionary pressure to vaccine-jumping mutations.

Note: Before anyone jumps on the above statement, I'm not trying to imply anything else. Vaxed folks who don't take reasonable additional precautions ARE a major source of spread COVID19. That's not meant as a comparative statement (unvaxed folks are ALSO a major source of spread).

Sure, fair point.

Nevertheless, vaccines do significantly still reduce your risk of infection. Agreed on the rest.

Would one know to get tested if they didn't have symptoms?