If you have a flat tire, you don't pull out the engine and start rebuilding it.
You misrepresented the problem. You then gave a bad way of fixing the actual problem.
You then gave a poor example trying to make your case that you are legit, and there is something to fear.
That is not a good analogy, because a flat tire is a limited problem, a malware is a full blown problem, since it can have total control over the computer.
Going with the car analogy, it would be like if the car is not starting, you cannot know if it's the engine, the pipes are clogged or what. And the car mechanic can look at the problem externally and see the broken part.
In a PC you can't look at the problem externally, unless you have a trusted OS booted from DVD, and even then you have BIOS malware and crap like that that could happen.
If a PC is exposed, it's exposed, you have to treat it like if it were some contagious biological virus in a lab , you don't just wash the jar with soap, sometimes you have to irradiate the entire building with if a contagious disease has escaped. And sometimes you have to quarantine an entire continent.
It's always about a threat model. You probably don't need to do this, and people who have smaller funds at risk. But some people here have millions of dollars at risk, and they have a different risk level entirely.
So the risk that is acceptable to 99.9% of the people is not acceptable for 0.1% of the people.