In this case the drawback is the off chance you get a strongly worded letter from your isp you can throw away

Pirating is not a criminal activity in my country.

It likely isn't a criminal activity in your country either.

Considering that HN slants heavily in the direction of the US, I'm not sure the latter statement is that accurate.

It's civil, not criminal in the US. Nobody's going to jail for copyright infringement.

You just might get a crippling fine.

Copyright infringement may or may not be criminal. While it may technically be for the operators of the streaming services, it is a civil matter from a user standpoint.

Having to remember to use a VPN? Hardly a drawback.

Well, there are really two drawbacks. Personal risk (which, as you say, can be well-mitigated) and the externality of other people being less well-off. Yes they could choose to make things that aren't copyable instead of things that are, but most jurisdictions have structures telling them that free copying of the thing they're making won't be tolerated.

Myself and several friends have several vpns and as we can mostly use up to 5 devices we share the logins, as required.

I was talking from a purely mechanical perspective.