This reads like classic 'it's not the same as X'. And an overestimation of actual human accounts on X in the Netherlands. Although yes, Dutch accounts on Mastodon aren't many, they are easily found, and interaction is up.

https://web.archive.org/web/20240713075513/https://www.digitaleoverheid.nl/nieuws/1-jarig-mastodon-overheid-blikt-terug-en-vooruit/

Dutch public sector has experimented with Mastodon for a year now. Pilot will run until December 2024. Started with 20 entities, now 40 active accounts. Plus is the easy recognition as authentic source (it runs on social.overheid.nl). They will open up to all levels of civil service in 2025. Good development.