I don't have time to dig up anything authoritative right now, but I assumed this was common knowledge and uncontroversial. It is precisely this kind of practices (reusing/selling/buying user and customer IPs - there are companies that specialize as brokers) that allows them their low prices while generally not getting blocked by services like Netflix, and I suspect it's also what's behind the move from NF.
> there are companies that specialize in brokers...
You're describing a botnet here. There are certainly organizations that will sell you access to their botnet, but I wouldn't describe them as uncontroversial, and I'd like to learn about ones that are structured as companies or that have as authoritative a reach as NordVPN.