Or maybe not such a great idea for Tesla to build one if they intended to take advantage of workers without repercussions?

No one takes advantage of them.

I have zero insight into how Tesla workers are treated here in Sweden, but it’s important to note that Sweden doesn’t even have a minimum wage law (it has been directly opposing such rules on an EU-level as well) because this should be negotiated between workers (unions) and employers. If Tesla continues to operate in Sweden without a collective agreement this model will break down.

Why?

He just told you.

Companies aren't allowed to merge into monopolies, why should workers?

Companies ultimately exist for the benefit of the public.