A cubesat approach may be surprisingly affordable (talking off the top of my head!), by interplanetary probe standards anyway.

And the devices would need to be very small to have any chance of meeting the necessary trajectory matching requirements.

Yes, it would take a few years to set up, but many space missions take years to get into place.

...or just say there are Mexicans out there.

It's astoundingly arrogant for anyone to assume that we are the only sentient species in the universe. Statistics suggest that there have to be many other planets capable of supporting life. What does seem more probable is that we will remain isolated from them and they from us due to the sheer distances involved, as well as time dilation.

...so a lot of stars have been sucked into oblivion already to amass 4 million Sols.

This is interesting - a recent study indicates that our Sun may have been formed as a direct result of the gravitational interaction of our Milky Way galaxy with a dwarf galaxy that orbits around it.  The dwarf galaxy is kind of skimming around us making multiple passes - it's first approach 5-6 billion years ago initiated a burst of star formation in the Milky Way that coincides with the birth of our own sun 4.5 billion years ago.

The link below shows a video simulation of the orbit (and break-up) of the dwarf galaxy around the Milky Way and how it synchronises with observed increases in star formation.

www.nanowerk.com/news2/space/newsid=55235.php

This is quite a biggie in the world of astronomy.

95% of the stuff in the universe is a mystery to us - Dark Energy and Dark Matter together are thought to make up 95% of everything.
They are called Dark because we haven't a frigging clue what they are.

OK, forget about them.
The "known" 5% of ordinary matter that makes up the stars, galaxies, planets (and us) is what is under discussion here.
That too has been an embarassment - because when we added up all the ordinary matter we could see it only came to about 2.5% of the universe.  Bugger.
It has long been suspected that the other half of the 5% was there, just spread out tenuously between the galaxies, but very hard to spot as it doesn't do much.

Fast Radio Bursts (FRBs) have come to our rescue as a kind of torch shining through billions of light years of space.
No, sigh, we don't really know what causes FRBs, either.
But what they are is very short duration (milliseconds) burst of radio energy, often from very far away across the universe.
These evidently started as a single almost instantaneous outburst, the radio waves from which then cross the universe to get to us.
Usefully, different wavelengths travel at different speeds when going through matter - even the very thin stuff that might exist between galaxies.
So, looking at a FRB the signal gets smeared in arrival time across different wavelengths - and the amount of smearing can be used to calculate the amount of "stuff" the signal has passed thorigh.
And, lo and behold, when the signals from a bunch of these quite rare FRBs are studied, that amount of stuff has been found to add up to the missing half of ordinary matter!  Quite an extraordinary result, actually.

So, whilst we are still clueless about 95% of the universe, we now have a better understanding of the remaining 5%, and all the stuff adds up to what we think it should given current theories - which is a major boost for those current theories. Maybe we do have some clue as to what is going on.  Yay.

phys.org/news/2020-05-cosmic-unveil-universe.html?utm_source=nwletter&utm_medium=email&utm_campaign=daily-nwletter

Well, it's a start.
And it is quite impressive that the right amount of material showed up in the FRB signals, although that could just have been a coincidence.

The Hubble Space Telescope sees a warped proto-planetary disc "flapping" as it rotates around its star, 1400 light years away from us.

futurism.com/nasa-hubble-observed-flapping-shadow-distant-space?mc_cid=3e194d84f4&mc_eid=092f9d027b

A 10-year time lapse of the sun from NASA's Solar Dynamics Observatory

As of June 2020, NASA's Solar Dynamics Observatory—SDO—has now been watching the sun nonstop for over a full decade. From its orbit in space around Earth, SDO has gathered 425 million high-resolution images of the sun, amassing 20 million gigabytes of data over the past 10 years. This information has enabled countless new discoveries about the workings of our closest star and how it influences the solar system.

phys.org/news/2020-06-video-year-lapse-sun-nasa.html?utm_source=nwletter&utm_medium=email&utm_campaign=daily-nwletter

In this 10 year time lapse video of our local star, every second is a day.