This is a creepy story. I agree it is best to keep your network secure. But, I feel there is always a chance that an employee who works for the network hardware company like an online baby monitoring company can always login to people's network gear even if the network gear is secured.
I read articles that Apple iCloud got hacked, and a lot of celebrities had to private photos leaked according to iCloud leaks of celebrity photos - Wikipedia , and Intel CPUs also suffered from Specter and Meltdown security vulnerabilities, so big companies can have security problems as well.
Maybe it would be more secure to use opensource free software and OS like Linux, your own PC and webcam and a more secure VPN to build an online baby monitor or security camera rather than buying an online baby monitor or security camera at a store.