A lot of the cost is involved with the training. AI companies got caught in the "stealing public work" cookie jar, and that's unlikely to be allowed to happen again at any meaningful scale. That means new AI cos are unlikely to form. They are more or less out of places to steal from without actually paying someone, and that will increase costs as well.
Facebook's LLaMMA is OSS only because of how far they know they are behind, and even to get there they got sued for stealing from pirate sites to train their model. Deepseek cost less (though not as little as they claim) mostly because they very likely utilized OpenAI to feed their model.
OSS is being stolen at an epic pace, and the licenses don't matter because no OSS dev or group has the money to take an AI company to court in this env.
None of this is sustainable nor "here to stay". Eventually AI will have to start training on AI content and that's where the death spiral starts because the hallucinations will compound and constantly add up.