That's a great point. I agree that's a danger, but please note DSA doesn't cede the control of content to government, but rather it creates an institution of (national) Digital Service Coordinators (DSCs) that decide whether a researcher's access to data is well-reasoned. In most cases that institution will be in a different country (the country of company's EU's HQs) than the researcher. That said, there could be malicious players involved, e.g., researchers and respective DSCs secretly recruited by a government to influence elections. This, however, sounds implausible, since in principle both the DSCs and researchers are independent from national governments.
Also, we can have depolarized recommendation algorithms. We don't need to go back all the way to timelines.