Why is it that everyone wants to post all the TDs public payment info out in the open?
If you do a bit of research about Crypto payments and transactions, you'd be able to find an answer to your question.
Two major reasons:
1 - Decentralization: The person sought to create a decentralized digital currency that was not controlled by any single entity, such as a government or financial institution. This was in response to the centralization of traditional financial systems, where a small number of entities have significant control over the flow and value of money.
2 - Trust: Traditional currencies rely on trust in central authorities, such as banks or governments, to maintain their value and legitimacy. Bitcoin was designed to operate on a trustless system using cryptographic techniques, ensuring that transactions could be conducted securely without the need for trust in a central authority.
Now you're probably wondering why I'm explaining this to you, its to explain that crypto is a way for anyone to make transactions
publicly, this enables the community to verify and validate transactions, that way, everyone is on the same page, everyone can verify that it was made since it's both out in the open while also being anonymous.
This person decided to post proof of his transaction, and rightly so, since this was exactly for this type of transaction that crypto was created/intended for.