If First Mover advantage is lost, whether it takes years or months, it will be gone forever. Yeah, Bitcoin will still be around. Hell, MySpace is still around, but The escape route from Bankster tyranny will have been blocked.
Goldman sachs and govcoin can never replicate some of bitcoins best attributes:soverign, immutable, no KYC. and extremely unlikely to replicate other features that make bitcoin so great : limited , disinflationary.
Once you know this , you will have no fear of these private blockchains.
Private companies are swell. You can even fine them.