PostNord has won the tender with the Swedish transport authority though and as such is the one they should use.
PostNord is the result of the merger between the privatized (but state owned) Swedish and Danish postal services.
But also – union rights and postal rights needs to be weighed against each other here – both are important
Union members should be allowed to go on strike, complete or partial as far as I'm concerned.
It just so happens that license plates are one of the things that gets blocked. Not because they are license plates but because Tesla is the receiver.
All of that is completely legal and acceptable. Employees of a company (PostNord) are joining together with employees from another company to fight against a company trying to avoid the rules on how the labour market works here.
There's no "civil servant" in play. Everyone is a worker.
Accept that it's a different culture, maybe not better or worse than yours but different. Here the labour market is a free market, the government doesn't regulate much, and it's up to negotiations directly between the participants of the market: employers and employees. For that a lot of companies agree under a Collective Bargaining Agreement the minimum bar expected for employers to respect when contracting employees. These CBAs complement the bare minimum legislation around the labour market from government, they are a cornerstone of almost all labour relationship instead of heavy government regulations.
Those are the rules of the game, Tesla is trying to break them, and worse, they brought scabs to break through the strike, which is really not tolerated in this culture. Because of that they have the sympathy of workers from other industries that Tesla relies on, since Tesla is trying to break the social contract of the labour market, other workers feel that is infringing on their own rights since it will create a precedent for other companies to also ignore the rules of the game.
This is what is in play, I hope you understand it's not your culture, it's ok to be ignorant about it but I expect smart people to also be able to learn a different perspective instead of keeping spouting their ignorance.
Sweden protects the rights of workers