If all they desired was putting one VPN tunnel inside another then it could be. But once you add in their actual intention, it can't.
That's not the issue (as far as I'm aware). The only 'purpose' for VPN1 in their idea is for the VPN to start there, instead of their home network. That would require them to have control at VPN1, which they don't.
In short, the Double VPN setup will not accomplish the intended result of hiding the entry-server.
It seems (talked to colleague) NordVPN has double-nat or something and offer that in their VPN service. Which as far as I understood mixes traffic so origin is harder to track, maybe that is sufficient idk.
So, I hereby thank everyone for participating in my paranoia
Having briefly read their page about "double vpn" it sounds like a lot of marketing babble.
They're either decrypting and then re-encrypting traffic within their network (which isn't ideal) or they're wrapping the initial tunnel inside a second one. In either case, anyone with the expertise/resources to hack NordVPN will be able to get as much useful info as if a 'single' VPN was being used. From the outside it'll look no different either as connections will still obviously be coming from NordVPN.
In short, any benefits are going to be extremely minimal at best. You might feel more secure/private but you won't be.