Even if Webb were to basically spot earth 2 5 light years away, I’d caution about getting excited for a radio chat.

Remember that life has existed on earth for something like 3 billion years, but multicellular life has only been around for 500 million or so years, humans in various forms have been around for about a million years, and we’ve only had radio for about a hundred years.

The vast majority of life that has ever existed on our planet has been single called organisms. Finding evidence of any life on another planet is huge news, but we should temper our expectations.

It’s way, way more likely for alien planets to have oceans full of plankton analogues as the dominant life. Considering the rest of this planet’s atmosphere is composed mostly of hydrogen, even their plankton would be weird by our standards.