Regarding the current situation, it's important to note that the block size of Bitcoin is actually limited to 1MB, not 4MB. However, the implementation of SegWit allows for more transaction capacity by separating some of the transaction data. This has helped alleviate some congestion on the network.
I thought this stood true:
A 300-byte transaction is 300 bytes on-disk and over-the-wire. Segwit just counts those bytes differently toward the maximum block size of 4M weight units.
If not, someone would have to correct the bitcoin wiki itself here:
https://en.bitcoin.it/wiki/Weight_units#MisconceptionsI apologize for the confusion. You are correct that the maximum block size in terms of weight units is close to 4MB. While the maximum block size on-disk and over-the-wire can be almost 4MB, this size is rarely reached in practice.
The actual size of a block can vary depending on the number and format of the transactions included in it. If the block contains a large number of small, simple transactions, the block size will be smaller. On the other hand, if the block contains complex transactions with many inputs and outputs, the block size will be larger.
It's important to note that the Bitcoin network has a block size limit to ensure the stability and security of the blockchain. This limit helps prevent spam transactions and ensures that blocks can be propagated and validated by the network efficiently.
The block size debate in the Bitcoin community has revolved around finding the right balance between scalability and decentralization. Increasing the block size too much could lead to centralization concerns, while keeping it too small could limit the number of transactions the network can handle.
Overall, the actual size of a block will depend on the specific transactions included within it, and the block size limit is a critical factor in maintaining the functionality and security of the Bitcoin network.