👀What is the maximum block time for a single Blockchain?

Under the premise of considering sufficient re-decentralization (where all participating nodes can fully transmit and package transactions).
According to the network latency time of 50-300ms across the 5 continents ( in ideal conditions ), and the transaction verification time (assuming ~5ms/tx)

Let ChatGPT create a mathematical model with parameters including:
1. The broadcast delay between nodes. This refers to the process of a transaction being uploaded from a single node to being accepted by all nodes in the network.
2. Transaction Execution and Verification Delays. That is, the legitimacy of the transaction is verified between nodes from the initiation of the construction to the verification of the transaction.
(ps: no consensus is taken into account, be it pos or pow)

The block time given by GPT is shown in the figure.
Although the actual situation falls far short of the illustrated standard.