The truth about VPNs? - Divisions by zero

So I’m pretty recent to the high seas but I’ve seen a few posts now about “stop relying on your VPN” and “people that think VPNs will protect them are naive” and so on. So since I believe knowledge is our greatest weapon/tool/super-power, can we get some answers regarding what exactly the doomsayers are getting at? ELI5 why VPNs wouldn’t protect your anonymity. Is it about logging? The country your end-point is in? Something more technical? Ultimately I’d like to be fully armed in order to keep making the best choices for my fledgling ship as it navigates the vast, stormy seas.

The thing with VPN's is that you're only shifting the trust from your ISP to your VPN provider. That provider can still see pretty much everything you're doing and your real IP, if they wanted to. To add to this, plenty of VPN companies have been found logging when they said they didn't. I would say either set up traffic for I2P, or simply go with an actually no logs VPN company like Mullvad, who's been battle tested and doesn't log, and you'll be fine.

People also say that because it's important to understand what a VPN is and does as well. It wasn't originally meant to be any sort of anonymity tool, the technology exists to make it seem as if your traffic is coming from somewhere else - which allows for things like remote work on a local network.

Skip Mullvad. They're removing port forwarding at the end of the month. I've been with them for years and unfortunately have to switch providers yet again.
Decided where to go yet? In the same boat here..
I am going to switch to AirVPN after some limited googling based on price, popularity, and port forwarding (the three 'P's). I dunno a whole lot about them but my main priority is just hiding my IP from movie studios and port forwarding. I don't need my traffic locked down like Fort Knox.