Declining Bitcoin dominance can happen in multiple ways, even as Bitcoin remains the largest digital currency by market capitalization. Here are some reasons and scenarios that could lead to this:

1. **Growth of altcoins**: If altcoins start growing faster than Bitcoin in terms of market cap, Bitcoin's holding will decline. This could happen if new successful projects are launched, or if altcoins gain wider adoption and more uses.

2. **Increase investment diversification**: If investors begin to further diversify their investment portfolios towards alternative currencies, this will lead to an increase in the market value of these currencies and thus reduce the percentage of Bitcoin acquisition.

3. **Technological development in altcoins**: Some digital currencies offer new technologies and features such as smart contracts, decentralized finance (DeFi), and non-fungible tokens (NFTs). If these features attract more users and investors, the market value of these coins could grow significantly.

4. **Wide institutional adoption**: If more companies and institutions begin to adopt and use alternative digital currencies in their businesses, this may contribute to increasing the market value of these currencies at the expense of Bitcoin.

5. **Change in Market Trends**: Sometimes, a change in market trends can occur as there becomes greater interest in certain categories of altcoins. For example, in certain periods the popularity of currencies based on social networks or those associated with decentralized applications may increase.

Although Bitcoin may remain the most popular and largest digital currency by market capitalization, the growth and development of altcoins could reduce its share of the overall market.