

I personally suspect that if aliens actually did show up to earth, they wouldn’t be content to remain in the shadows.
Basically, the native life is the only thing that would be of interest. we (that is life,) are the only things that are actually unique to this particular system. If it’s simple curiosity about things, they could study us from a distance, without ever revealing themselves to us (or the government.)
Which leaves a few reasons for why they’d come here:
- Genocidal freaks who have some biological or cultural imperative to kill everything that’s not them.
- Space Mormons coming to share their faith. -Space evangelicals. They’re like Space Mormons, except turn into the first group when you politely decline.
Either way… we’d know they’d be here.

Pretty sure the prime directive says “if they’ve nuked themselves hundreds of times… DONOTGOTHERE!!!”
(Of course they went there. What could go wrong?)