I can't understand why government offices for many countries are still on Twitter. At least Germany has their own mastodon service, but my home country Finland still uses Twitter.
False premise, most people are not on Twitter. Outside of Japan and the US, comparatively few people use Twitter.
Yet, all the politicians (both government and non-government), media personalities, and many state run institutions actively run Twitter accounts. So it is one of the primary ways to understand what they are saying.