According to updated Eurovision rules, artists aren’t allowed to wave any pride flags on stage. While most pride flags have already been banned last year (Nemo, for example, wasn’t actually allowed to wave the non-binary flag), this now even includes the six-stripe rainbow flag.
However, before last year, it wasn’t something very special to also wave a pride flag or have one in the Greenroom.
As I’ve understood, previously, all flags of non-competing countries, e.g. Palestine, were banned on and off stage, for the artists as well as for the audience. The new rules allow the audience to wave any flag that is not forbidden by law, while the artists (for some reason) have been restricted to only use the flag of their participation country, i.e. not even necessarily their own national flag.
https://edition.cnn.com/2025/04/30/entertainment/eurovision-2025-flag-restrictions-scli-intl/index.html
Hopefully, the Dutch broadcaster is successful with it’s objection against restriction of non-territorial flags, like the different types of pride flags.