Not sure how this would have bothered their national team. Furthermore, how is the recent Hungarian legislature's attacks on the LGBTQIA+ community not extreme cases?The controversy for the rainbow coloured stadium is not because they just randomly wanted to colour it this way for once, but because they wanted to colour it against Hungary, where the parliament recently passed an anti-LGBTQ+ law.
On one hand, it's justified that some people want to show solidarity with people affected by the law, but we are talking about a sporting competition where sports should be in the focus. There have been (justified) measures in sports against governments in the past (for example sporting boycott of South Africa because of Apartheid), but that should be kept for extreme cases.