For sure. There was an air of sarcasm to that. Shooting a microwave bean 100 million miles doesn’t seem as hard as focusing 360 degrees of Satellite beams in one direction, but I’m sure it can be done.

Now, just manufacture about 100 million of those, flip ‘em over and lash ‘em together. The Dyson sphere is closer than we think.

Oxygen. Specimens trapped in ice or tar or are quickly engulfed in a muddy river bank are sealed in an airtight tomb where things that would decay them can’t reach. Namely oxygen to fuel bugs. So, they sit.

Things that die in a warm/wet climate crawling with trillions of insects and scavengers won’t last a few hours.

We know so much about the past largely because bad things happened a lot. There were at least five mass extinction events that nearly killed everything. Those are easy to find if you dig in the right spot. Harder to identify and locate are the isolated events of mudslides and flash floods and so on. With that in mind, when digging, you want to locate the layer of dirt relative to your timeframe and root around in it. If you’re looking for a needle in a haystack, you’ll rarely find it. If you’re looking for a planet killing event, you’ll find that layer easily, AND the specimens trapped under it. So, paleontologists spend a lot of their very valuable time digging easy and well known places like the black hills, or riverbanks in Canada. Because of all that, we have lots of fossils from specific eras and almost nothing from others.