I recommend focusing on the monetary benefits that tagging will bring.
For example, if tagging is used to define the environment (Dev/Prod) then do focus on the impact on financial reporting or tax implication of Dev versus Prod. In many countries, some dev costs can be claimed back. For reporting, knowing what is prod allows to really report things correctly in the P&L.
You need to put yourself in the executive’s shoes who will spend the money to get tagging, and explain the ROI of this initiative.