Understand your sympathies.  My old cat is a rescue as well.  Carried him home as a tiny kitten from Sand Pt.  But adoption isn't the answer for the feral cat scourge--from 47 to 100 million per ASPCA estimates.

Most folks don't have enough patience to tame a feral cat (in some cases these cats simply can't be tamed).  But consider:

Most households want kittens, not grown cats.  Feral cat sex ratio is 67% male to 33% female in reproductive-age cats because of birth-related differential mortality in females.  Each reproducing female can produce from one to six litters of up to 12 kittens each year.

OK--based on an average of the ASPCA estimates, 0.33 x 72.5 million = about 24 million reproducing age female cats in a given year.  Average 3.5 litters x 6.5 kittens/year, assume only 1/4th survive to adoptable age: that's about 136 million new 'adoptable' feral kittens each year.  Next year, rinse and repeat.

There are only ~128 million households in the US.