Avi Loeb, is the Harvard astronomer, author of Extraterrestrial: The First Sign of Intelligent Life Beyond Earth, who argued that Oumuamua was an extraterrestrial light sail. At SciAm, he writes,
As discussed in my book, our inability to continue collecting data on `Oumuamua, which is now a million times fainter than it was during its close passage to the sun, limits our ability to make further progress in deciphering its nature. Our best path forward is therefore to use survey telescopes like Pan-STARRS or the forthcoming Vera C. Rubin Observatory to identify other weird interstellar objects as they approach us, and then deploy a small spacecraft equipped with camera along their predictable path and take a close-up photograph of them. As the saying goes, “a picture is worth a thousand words.” In this case, it would allow us to distinguish between a rock and a technological artifact.
The experience would be similar to walking on the beach and finding mostly seashells and rocks that are naturally produced, but every now and then stumbling over a plastic bottle that implies the existence of a civilization out there. Whereas the traditional search for radio signals is equivalent to speaking on the phone with a living counterpart, finding a “message in a bottle” resembles receiving a letter in the mail, which could occur after the sender had died. It offers a much more powerful peek into the past existence of dead civilizations, and provides the space analog of an archaeological search for relics left behind by cultures that are not around anymore on Earth.
Avi Loeb, “To Qualify as ‘Scientific,’ Evidence Has to Be Reproducible” at Scientific American (March 1, 2021)
Okay but it was never clear why Oumuamua was supposed to be ET anyway. More Oumuamuas would not make it more likely.
See also: Tales of an invented god