We can’t even detect our own signals beyond a handful of light years, even the nearest star system is questionable. But let’s say it’s 100 light years, even then that’s one ten millionth of our own galaxy, and 0% of the universe. So the idea we can even tell if anything is out there beyond thousands of star systems put into obviously artificial arrangements or entire galaxies rearranged wholesale is nonsense.
More importantly, just look at what our signals have been doing, initially they were quite omnidirectional and high power as receiver technology barely existed. As time progressed, we focused on efficiency as energy in the universe is limited and for any amount you can do more if your efficiency can be higher. Hence our radio signals now are much more directional and lower power. But if this trend continues, we may not ever be able to detect advanced signaling from more than the same bubble we have now as improvements in efficiency keep up with or outpace detection technology.
Furthet, the same principle of efficiency that makes evolved life forms here almost god like in their abilities means the entire idea aliens would use the output power of a large star to just broadcast so primitives could hear is insane and counter productive to basic reasoning. Same with creating a Dyson swarm to harness the power of its star, it would be nearly identical to a star simply hidden by dust. Plus if faster than light communication exists, in some reference frame of instant communication, then moving stars or galaxies around is an enormous waste of energy that would never happen. If faster than light communications is not possible, advanced life would likely act on a pace even faster than our fast paced societies and there can be no cohesive society, no coalition because the time delays are ultimately isolating making life invest into only a few systems or at the least, spread extremely slowly. Like our bodies that now use massive amounts of resources simply on processing and thinking as opposed to our single cellular predecessors, and like our technology that has moved from nearly 0% information processing to a significant percentage, any sufficiently advanced civilization is likely spending the majority of its energy budget on efficient information processing tasks and the entire concept of needing to burn unthinkable amounts of a precious resource on mundane brute force tasks with no benefit is unfounded.