The title really misleads -- cats can be great at urban mouse control. But for urban rat control you need something bigger.
"Feral and free-ranging cats are the leading human-caused threat to birds in the United States, killing an estimated 1.3 to 4 billion birds annually." (Google)
I am excited that researchers can reach these conclusions in 2018. This is certainly an excellent way to use grant money.
I've had neighbors who will occasionally leave out bowls of water or food. I've known people who took on responsibility for several cat colonies and had a "nightly feeding route" for them. But around here, once a colony is established, they do not seem to have trouble finding discarded food, or chasing bugs in the lawn.
I'm sure the authors are dog people, because their solution is remove cats rather than bigger cats. Dog people always seem to have an irrational hatred for cats.