The congestion on the Bitcoin blockchain primarily stems from two factors:

1. Limited Block Size: Bitcoin has a maximum block size of 1 megabyte (MB). Each block contains a certain number of transactions, and when the demand for transactions exceeds the block size limit, a backlog of pending transactions occurs. As a result, transactions with lower fees may take longer to get confirmed or may even be left out temporarily.

2. Increased Transaction Demand: The popularity of Bitcoin and its widespread adoption has led to an increase in the number of transactions being processed on the network. More people using Bitcoin means more transactions competing for limited space within each block. During periods of high demand, such as when there is a surge in trading activity or when there are significant events impacting the cryptocurrency market, the number of transactions can exceed the capacity of the blocks.

To prioritize transactions and incentivize miners to include them in the limited space available, users can set a transaction fee. Miners typically prioritize transactions with higher fees as they are motivated to include those transactions first, as they receive the fees as rewards for their mining efforts.

When congestion occurs, users who want their transactions to be processed quickly may increase the transaction fee they are willing to pay. This higher fee helps their transaction stand out among the many waiting transactions and improves the chances of miners including it in the next block.

Efforts have been made to address the congestion issue. One significant development is the implementation of the Segregated Witness (SegWit) upgrade, which separates the transaction signature data from the transaction data, effectively increasing the block capacity. Additionally, layer-two solutions such as the Lightning Network have been introduced to facilitate off-chain transactions, reducing the burden on the main blockchain.

It's important to note that congestion on the Bitcoin blockchain can vary over time, and periods of high demand and congestion are usually temporary. However, it highlights the need for continued research and development of scaling solutions to ensure that Bitcoin can handle increased transaction volume efficiently.

Ordinals have contributed to a bigger usage of the Bitcoin space and therefore making transactions within Bitcoin's Network more expensive, this is not something new as it is an indication of high demand on it's network.

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