This fact alone makes the comparison you’re trying to make pretty silly. You have far, far more to fear from the country from which you’re a citizen than the company for which you’re a customer.
Read more history.
With private security companies, private jails, private utilities, the harm both can and will do, is practically the same. And with the boundaries of "private" and "government" becoming more opaque (like private tech companies deciding who is to be detained and who not; who is allowed to access their money; or do their jobs, etc) the difference is even more theoretic.
A government that has absolute power over a company/sector, can (and will, in my belief) use that power to make the company/sector do it's work. Making this company/sector just as dangerous as the company.
If I get mistreated at an airport (of a democratic country), and the agents doing the mistreating are civil-servants, they (or their chain of command) are democratically held accountable. But if they are employees of Acme-Security Inc, granted the right of violence by the democratic government, there's nothing I can do, no-one to appeal to. Both cases are something I, an individual, cannot do anything against. I am mistreated anyway.
https://en.wikipedia.org/wiki/Banana_Massacre
Read more history.
Also, governments consists of a large amount of human each acting for their own benefit. Assuming they can easily collectively united as a single force to use violence to harm all citizen (on the topic of privacy, it really is the case) suddenly is wild.
On the contrary, for a limited government, it very likely will result in using the monopoly of violence to provide extreme capitalism style IP and private property protection which results in dominating power of large companies. On the other hand, every bit of history demonstrated you can never maintain monopoly of violence if you are really against people.
Monopoly on economic is strong because it can be guarded by violence, while violence cannot be easily guarded by itself within a country (unless AI overlord really comes).
Read more history.