A few things, Jacques was found cause the system showed up as "Independent" on the galaxy map. So amongst all these grey dots there was a bright yellow one. FD forgot to reset that. And it still took a long time.
The capital ships were found because there were clues and directions left behind. It really wasn't that difficult once we started finding the clues.
Barnacles were in the game for months until someone found one. And once we knew they were in/around nebula's others started being found too. I suspect we've only found a small portion of them. Not that it matters, they've all been the same. The Unknown Artifacts were in USS sites. And not that uncommon either. Wasn't exactly a needle in a haystack. Unknown Probes WERE a needle in a haystack and took forever to find. The first bunch were in highly guarded military convoy's and we only managed to get a few of them. Took months before someone found one orbiting an Ammonia world, and they're fairly common there. Surprised it took us that long, frankly. The Thargoid/Ammonia world connection has been known to us the whole time. It made sense. Plus, the devs confirmed there was an easier way to find them other than the convoys so we were intentionally looking for USS's that had them.
The Thargoids would hyperdict you randomly around the Pleiades. You didn't have to have any item in your hold. That was fake news.
The INRA base? Yeah that one stinks. Within a few days after being revealed, someone knew EXACTLY which planet to look at and apparently where on the planet to find it. We've seen how long it takes to find bases on these planets with the Formidine Rift bases, and it's longer than a couple guys spending a weekend.