It'd be like if counterfeit designer clothes were actually indistinguishable from the "real" ones, and arguably better made in some cases.
Also a better analogy would be that you can make 1000 copies of the Mona Lisa in whatever way you want, they will still be just copies and they will be worthless.
Your analogy is more like getting the Facebook database and spinning up 100 clones of it, all with 3 billion users. Now "Facebook" has 300 billion users. It could have a trillion or a quintillion right? Or an infinite amount. But what does that even mean if the actual 3 billion people only use the original network? It means Facebook is still Facebook, and forking it, in terms of how it affects the network it its value, is relatively pointless.
You're not making a real point.
If a clone of Bitcoin is identical to Bitcoin then why does Bitcoin trade 25x the price of a clone? Your argument would cary weight if the protocol and price facets were similar. The market says otherwise.
Because humans are stupid, faddish creatures.
The market can remain irrational longer than you can remain solvent.