We now know that most EU-countries support Equal Treatment - of paper and e-invoices - from a VAT-auditing angle. This is great progress.
Some may still need clarification - what does ET mean? In all essence it means that: Transport IS irrelevant. From this follows that auditing can treat all invoicing in the same way.
Of course it makes common sense - VAT audit is taking place in the corporate environment today and tomorrow - and it will be easier and finding less fraud, the faster we move away from paper. That is the only difference - and the very reason why ET is in everybody's interest as it makes it easy to migrate - not difficult as for example mandatory digital signatures do.
Will this lead to a slower harmonization of VAT auditing? I do not think so - on the contrary it will be possible to move faster also in this field - as ET will bring volumes, pressure on roaming, interoperability and use of common standards.