We live in a society with deep dependency chains on technology we can't possibly understand as individuals, that much is true
But all of those technologies are subject to independent auditing and regulation to make up for that lack of verifiability on an individual level. It is technologically feasible to apply that kind of standard to computer technologies, and in fact I would argue that it's much easier than it is for a lot of other kinds of technology we rely on. That our willingness at a political level to do so is lacking is a corruption issue, not a feasibility one.
Because we don't have the time needed to do the audit nor necessarily the access, while auditors and regulators have both because of legal backing and the fact that it's their full time job
The entire point of an independent audit is to throw an expert at the technologies in question at the point of the supply chain they are tasked with auditing in order to better understand it than a layperson could and make an assessment that provides the public with the benefit of their expertise. Not everyone can be an expert on everything, but experts can check each other's work and report on it publicly.
The drum on my washing machine is approved by Underwriters Laboratory and regulated by ADA requirements. The bridge I walk on was designed by a licensed professional engineer. Software is just about the only profession left with absolutely no accountability to anyone.