The reason for the growth of any asset is the excess of demand over supply, this applies to any type of product without exception. It is much more interesting to understand the causes of the resulting imbalance.
Usually, when talking about the future of crypto, they focus on the usefulness of blockchain technology. The technology is really useful, but to call it the only reason for the current growth of the crypto.

Here are the main factors:

Actions of institutional investors. For example, at the end of 2020, only Ruffer Investment bought Bitcoins for $745 million. Later, Tesla announced an investment of $1.5 billion in BTC, although the investment itself was made earlier, but this informational event also affected the Bitcoin rate, and hence the rest of the crypt .

The never-ending hype. Bitcoin is constantly storming new heights, more and more ordinary people are investing in crypto. Moreover, the crypto is held, not resold. In the context of increasing interest in crypto, this exacerbates the situation with the balance between supply and demand.
Distribution of "helicopter money" due to the pandemic. People are trying to protect capital from inflation and earn money, as a result, money is sent to the stock and cryptocurrency markets.