Round numbers: an order of magnitude less risk of symptomatic infection. 2-4 orders of magnitude less risk of hospitalization upon infection. Near-elimination of the risk of death. Near-elimination of the risk of Long Covid (an issue with at least a quarter of sympatomatic infections without vaccination) because vaccination severely blunts our immune over-reaction to infection. Those massive reductions in risk are a hell of a tangible benefit!
There's a major difference between "less effective against the spread of Delta" and "doesn't protect much against Delta". Reality is the former, you imply the latter. In my province, 97% of hospitalizations for Covid are not vaccinated. It's obvious that vaccination has a major impact.
An important thing to remember is vaccines do not confer immediate peak efficacy and whatever peak efficacy is reached, quickly declines, as evidenced by the stated need for booster shots. Therefore, any claims of “X” protection of a vaccination are dubious at best. Further, any vaccine that suppresses one’s immune system may be beneficial against Covid, but not against other viruses or bacteria, for that matter. As we know, Covid is not the only infectious pathogen out there, right?