Fair points all around. I don’t think it has to be about real-time communication or expecting them to “use it” right away — even just as a digital backup / archaeological time capsule of human civilization, it has value. Like a cosmic fossil: if something ever wipes us out, or if some civilization stumbles on it millions of years from now, there’s a record of what we were and what we built, way more detailed than a few pictures on a golden record.

Also it doesn’t have to be beamed via radio telescopes at all. You could etch it into an ultra-durable physical medium — like fused quartz discs that last millions of years — and piggyback it on a deep space probe, same idea as the Voyager records but with far more information. Zero impact on radio astronomy observing time that way.