The reality is that if the Republicans take over, things won't be that bad for non-target populations. And, from the perspective of non-target populations, things won't look that bad for target populations.
America can just keep doing things the way it always has. Structural oppression, roadblocks, gatekeeping, policing, judicial oppression, etc.
Camps would be obvious and easy to fight. Instead look to both Jim Crow and the post-Jim Crow War on Drugs era to see how it could work.
They're already doing that with women's rights and LGBTQ+ rights. It's not a full out ban… that's stated explicitly in their guidance documents. It's not about making us illegal, it's a series of byzantine rules and laws disconnected across the country to make it extremely difficult and confusing. That's an option you can't fight against directly. But it's an option that keeps US fighting just to survive. That's their strategy.