You have a point - the state's authority to arrest people is a huge hammer that should never be brought out unless absolutely necessary. That's why Bay Area officials aren't using it. Nobody in my county has been arrested for not staying at home, and last I heard only a single person outside of Santa Cruz has been.
It is a huge hammer and this is a huge problem. We normally arrest people for endangering the public. People not abiding by the lock down are clearly endangering the public. They should be arrested.
I don't see any slippery slope or danger of totalitarian take over. The virus is inherently time-limited.
The Patriot Act was time-limited too, until we found more reasons to keep it around after the limit. We should be skeptical of this kind of thing, although I'm not so absolutist that I'd say it's never worth it.
The Patriot Act was not inherently time-limited. A virus will have an end at some point through a vaccine or therapies. Terrorism does not have any end. In fact it is timeless.