The SEPA Instant Credit Transfer scheme introduced in 2017 introduced 10-second transfers. Not all banks are participating yet, particularly in (south-)eastern Europe, but it's a fast growing share, and in my home country (the Netherlands) just about everyone does.
All of my SEPA transfers after 2017 took days and none of them involved banks in (south-)eastern Europe. But it's good to hear that things are improving.
