So "little-to-nothing" is an understatement and even a fairly small percentage reduction means a lot when it applies to hundreds of millions of people. The "decrease of transmission" is really only talking about "If I'm in a room with a COVID positive person, will I get sick?" and nothing about population level "decrease of spread" because there are less contagious days per person per infection.

from https://www.nejm.org/doi/full/10.1056/nejmc2106757

"We provide empirical evidence suggesting that vaccination may reduce transmission by showing that vaccination of health care workers is associated with a decrease in documented cases of Covid-19 among members of their households."

So vaccines not only provide protection against worse outcomes (including the parent commenters loss of smell), but they also reduce spread, even if just through the fact that a shorter infection means less opportunity.