Sorry if this seems rude, it's not meant to be, I'm genuinely curious.

I understand (and support) opposition to contact tracing by badly designed technological solutions, but what is your argument against manual contact tracing? (actually asking people one-on-one who they've been in contact with if they test positive to Covid-19)

I'm just after your reasoning. I promise I won't deride your decision in any way (and I hope others refrain from doing so as well). People react differently in extreme situations, and I try to be aware of as many different reactions as possible, and possibly try to understand the reasons for those reactions.

This does happen (manual contact tracing) — at least it did when I had COVID-19 in March.

A substantial part of the US population will not cooperate.

Yes, but why? It may be a valid reason, but I don't know what it is.

Basically, the government takes way more information than it is entitled to already. And then doesn't secure it. Look up snowden leaks, opm breach, etc etc. Rereading the 4th Amendment might be helpful as background as well.

Lack of confidence in government and authority is my guess?

In case you didn't see the riots last week, many US people don't trust the police. If somebody knocks on your door, how do you know what their real motive is?

Are they there for contact tracing, to serve a warrant, to tip off ICE, or to plant something?

After all, the CIA used vaccines as a ruse to hunt Bin Laden.

I don't think police does contact tracing - usually it's the civil employees of the "hygiene office".