Will they allowed to go higher?

It's unlikely that governments would intentionally allow altcoins to devalue central tradefi. There are a few scenarios where altcoins could potentially challenge the dominance of fiat currencies:

1. Cryptocurrency adoption: Widespread adoption of cryptocurrencies could lead to a shift in the global monetary system, potentially reducing the importance of fiat currencies.
   
2. Central bank digital currencies (CBDCs): Some central banks are exploring the development of their own digital currencies, which could potentially coexist with altcoins and reduce the influence of traditional currencies.
   
3. Decentralized finance (DeFi): The growth of DeFi platforms, which offer lending, borrowing, and other financial services using cryptocurrencies, could potentially disrupt traditional financial systems and challenge the role of fiat currencies.
   

So. will they 'really' allow it?