Whilst I don't disagree with a number of your other points, I note that there are some significant factual errors. Rather than just 20 financial organisations in Europe, every ACH transaction in Euros in Europe (not just Euro countries) are now 20022 based. In context, that's 37 bn p.a., 1.5x US volumes, across 9000 banks and 50+ processors.

Its also not just limited to either Europe (many, many countries such as Japan, China and Brazil), or ACH (Swift; securities now adopting; and many card systems such as those in Russia or India use as well), or even just payments (einvoicing for example).

The recent Fed sponsored business case, suggested there may be no financial case - but then again, which standard ever did create a positive case?