What the hell is Bitcoin Cash and all these other branches, soft-fork, hard-fork. IMO Bitcoin would have been at $1m a coin by now if you didn't desecrate Satoshi's original vision.
IMO Bitcoin is less valuable today if there's no protocol upgrade through soft-fork.
Does that make it an invincible currency? Not really. Plenty of exchanges were hacked, wallets get lost and there's no way to recover them, there's millions of coins I would say > 3,000,000 that are gone.
The problem you mentioned is due to user, wallet developer or exchange mistake, not flaw of Bitcoin protocol.