I'll give you that not all vaccines are 100%. But the only thing this "vaccine" is kind of effective is lowering symptoms.
Not necessarily on either catching nor spreading. They have no data to show cases in vaccinated people due to the fact that the vaccinated don't know they have it and therefore don't get tested. So, it is possible, even likely, that the vaccinated are spreading it at a higher pace than the unvaxed due to no one testing the vaccinated. They get to go willy nilly wherever without testing, but the unvaxed have to show proof of negative before traveling, going to work, enjoying a concert, etc... but who knows how many vaccinated people are spreading it in those places?