Yes, you're right, it's not possible for "a company" to commit fraud and still be a company, right? If the world worked like that, you would expect to find many examples of companies committing fraud.
And you'd never find a bank like Wells Fargo committing fraud for money, right? Because surely they wouldn't be a bank?
And you'd never find a company violating its own user privacy rules, like Facebook, because they'd surely be out of business, right?
And you'd never find a major phone company billing people for things they didn't have the right to do, because surely AT&T would be out of business, right?
The fact is: "most likely" and "probably" and your uninformed best guess about what happened is not knowing.
I'm not sure why you would think that the only reason that I would think that Netflix restarted my subscription in error is that I'm a "non-techie" (and ugh, what an odious way to try to dismiss someone) who thinks "the computer decided on it's [sic] own." It tells me a lot about your understanding that you can't imagine many scenarios where the interaction of a complex, mostly non-technical system of product design, business decisionmakers, microservice integrations, several apps on hundreds of distinct platforms might behave in an unexpected way that treats consumers unfairly, with varying levels of intention or neglect at different layers.
As the consumer, I'm getting charged the money and I'm the one who needs the justification to indicate that it was authorized. I disagree with your perspective that "Well, they're a 'company', therefore they must have a good reason to charge me, I better pay it".
I do, in fact, think it's "most likely" that someone did... something... on a logged-in device that restarted the subscription. However, I think it's very unlikely that that involved presenting a new billing agreement that they agreed to, or providing the password to my account (remember, this is a subscription that was cancelled, not suspended or paused or frozen or any other kind of seemingly-temporary measure--since Netflix doesn't offer a way to remove accounts, it's the strongest thing I can do to sever my business relationship with them). If the logic is unintentional: an edge case of a logged-in device where that particular app on that platform sent the wrong cookie when starting a stream, etc., then Netflix not caring to investigate and solve it is because they're happy to collect revenue from erroneous and unjustified subscriptions in the hope that consumers won't notice or fight it; which is gross. If the logic is intentional: to obscure the fact that whatever action the user takes results in a re-subscription; then it's gross and possibly illegal (dunno, not a lawyer, and my definition of "crooked" might include things that aren't yet against the law). Either way, they are likely to keep doing it until forced to stop, because your naïve perspective that companies can never do anything wrong is absolutely incorrect.