What I'm saying is that your mindset here is flawed for this kind of debate.
A majorly strawman argument here. For starters the Minoans were incredibly advanced. Then you have the pyramids, where if they weren't built by aliens then there was an advanced civilisation there, and if they were built by them, you still have an advanced civilisation there.
Yet practically everything from those civilisations is gone. Then you have the steam engine- first built by Archemedes. Gone. It took us 1700 years to rediscover it. We still don't know how the Romans were simultaneously able to blow 2 layered glass vessels- for now that information has been lost.
You talk about all the info we have- if we get hit with enough electro magnetic radiation in one hit- something like a massive coronal mass ejection, like the one which hit us in 1850, then all that information can be kissed goodbye.
Humanity has been "wiped out" multiple times in the past to varying degrees. Yet every single time we resiliently bounce back. Because humans are always curious, there will always be historians. When humans in the future get curious, then they will always want to find artefacts- the more complete and the better condition they are in, the better.
Sure there'll be evidence of toys in the future that aren't sealed up, but they're be a case of finding half an arm or a fist somewhere where historians are left puzzled as to what each individual bit is for, especially if they only find that bit.
A toy sealed in an Acrylic case though, has the best chance of being intact for them to study.
In other words, we should avoid using items as evidence in court cases the moment they don't serve a function of being looked at in everyday life then. Considering that historical artifacts, or evidence, work the exact same way as evidence used in a court of law, that's exactly what you are saying.