As the VPN market has shown, filtering by IP address does not filter by country and therefore does not fulfill a contractual obligation for limited distribution. Whoever claims otherwise is misinformed or deliberately lying.
Also, very important note: unless the BBC has established offices/activities in Belgium, there's nothing to be sued about. As a british organization abiding by british laws, they couldn't care less what the Brussels copyright mafia has to say in belgian courts. The only exception to this i can think of is when the US copyright mafia gets involved and they will bribe (see The Pirate Bay trials) and push for foreign arrests (see Kim Dotcom arrest) because US government is subservient to their interests.
Now for my personal opinion: fuck copyright, fuck "rightholders", fuck the police and fuck the mafia. Just abolish money and private property: we have enough resources for everyone to live decently if we don't concentrate them in the hands of wealthy fuckers who'd like us all to suffer for their greed. Let the people who want to create art do so, and let the people who want to enjoy it do that too.
Netflix is global, Prime is on its way, and Disney and HBO are trying. But a BBC streaming service is going to outbid 10/10 times because they can't afford to buy North American streaming rights when they don't have a (viable) North American service.
The BBC would survives because the law mandates UK citizen pay for it. But any non-subsidized local service would be dead in the water.
More seriously, Netflix business model is deeply broken. Trying to replicate that at all cost with public money is doomed to failure. A decent alternative would be the Global License [0] which was at the center of french public debate 15 years ago. It's more or less the same model, but without trying to feed ~parasites~ shareholders on the way, and without stupid competition between 5 different streaming services you all need a subscription for.