Legalities aside, you need to look not at the model quality but at the infrastructure needed to scale these models from tens (now) to hundreds (soon) of millions of users. Only a handful of companies actually have the resources and funding to do that. That's what these huge valuations are based on. These companies are gearing up to scale to these levels. That's why they are spending on data centers. Whoever has access to those data centers gets to tap into the revenue stream of people using models running on those.
The market for frontier models is roughly split between OpenAI, Anthropic, and Google. And then you have companies like X/SpaceX, Amazon, and Microsoft being more successful with their infrastructure than their AI products and companies like Apple, Meta that have the money and the aspiration but are so far not really managing to be very successful with their AI strategies.
Deepseek is just very poorly positioned to capture a lot of the enterprise revenue in the EU or North America. But they might become very dominant outside the US/EU. And of course China itself is going to be a huge market and equally unlikely to want to be depending on US owner AI companies.
Personally I see no difference between China and America in terms of risks of them embedding "backdoors" so to speak, but I disagree when people claim that open-weight models are obviously safe just because they can be ran locally.
Perhaps, but that's also a good way to lose users+reputation as there's no way to control when said malware is generated. Once the first instance is discovered cybersec researchers will have a field day reproducing it and showing the world.
Sure, you can self host a non-frontier OSS model yourself; including Deepseek. And no doubt some people will pay one of the companies I mentioned to rent the infrastructure to do exactly that. Much of the rest of the world will be paying directly for direct access to the frontier models.
As for the legal/compliance stuff, I recommend you don't take any big decisions on that front without consulting lawyers. My understanding of that is that most serious companies in the EU have to take these topics pretty seriously. I'm sure in the US, hosting all your data and secrets in Chinese data centers isn't a whole lot less controversial.
The Chinese could of course choose try to match the current levels of investment Google, OpenAI, Anthropic, etc. are putting into local infrastructure. But as far as I know they aren't and there are probably a few political blockers for that.
Without infrastructure, their role is being a niche player in these markets. It doesn't really matter how good they are if they can't scale to most of the market.