There are many, many unmanned missions happening now making amazing discoveries. Cassini was nothing short of mind blowing.
I'm somewhat sympathetic to your claims, and I wish more people were intellectually curious, but there are very likely more people in absolute numbers performing scientific research now than ever.
I'll believe it when I see it. For now the Voyagers are the only thing out there that are expanding our envelope of influence, everything else is just data and will eventually evaporate.
Think about it from a non-solar system perspective. Nothing we've done since Voyager has had any effect outside of our solar system and if we don't change our attitude it is quite likely that nothing ever will. Everything else we've done will long term only be a little bit of radiation, some of it structured but so far below the noise floor it will be unrecoverable.
IMO, throwing out more Voyager like probes is not really the next step in humanities evolution towards space. It was a good step in the 70s, but now we're working to the lay the foundation and hope that one day space travel can be nearly routine as air travel is today. Higher volume of launches, bringing down the costs, etc... will allow hundreds and thousands of Voyagers to be sent out aimed at specific, distant locations.
You may dislike Musk, but SpaceX is pushing getting to space forward.
There's every possibility that neither Voyager will ever arrive anywhere ever again. If they do, it's going to be after our galaxy collides with another, and the place they arrive at may not even exist yet.
While the Milky Way galaxy is on course to collide with Andromeda galaxy in 4.5 billion years, that will not make Voyager's arrival anywhere more likely, since the stars are far enough apart that they will not be affected.
My understanding is that it just makes it less predictable once that happens. We don't know exactly where all those stars are, and it gets chaotic once they start interacting.
It probably is a _bit_ more likely as well, you suddenly have ~2x the stars near you and some of them are moving much faster relative to you, it's just not a sure thing by any means.
Well so would be picking up radio signals like the ones we emit.
And while the probability that someone will be able to pick these signals up is low, it is still almost infinitely greater than that of someone finding one of the Voyagers out there.
Launching more Voyagers is like tossing heavy metal disks into a random deep-sea part of the ocean and hoping one of them lands next to a benthic creature that can miraculously appreciate its significance. Not only is God more plausible, so is the Flying Spaghetti Monster.
I'm somewhat sympathetic to your claims, and I wish more people were intellectually curious, but there are very likely more people in absolute numbers performing scientific research now than ever.