A few potential answers
It's really not that difficult to find potential answers to your rantings.
1). Who defines what is filtered
Unspecified as yet - so if you don't like it, don't enable it.
2). Will the project creep
Speculation - legitimately complain when it does.
3). Who will pay
Not beyond the realms of possibility for those who wish enable it to pay for it.
4). Why should the UK online populous as a whole kowtow to a few outspoken individuals who seem to not know:
If it's optional - it's hardly a problem... how did you manage to quantify "a few"?
4a). how to be a parent
You merely need to breed to be a parent. Being a responsible parent takes skills that not everyone can manage.
b). not know how to install Net Nanny
Maybe it's a few people that realise that a reasonable proportion of the population can't install Net Nanny. Just because you can, doesn't mean that everyone can.
5). Anything implemented will immediately be circumnavigated by any averagely intellectual 12 year old, whilst on the machine in their bedroom, left their by said parents assuming the machine to be 'safe', VPN routing through the Ukraine to watch videos of the Taliban shagging donkeys, whilst the rest of us continue to be burdened by this shit
No one said that you had to be burdened. Don't be under the illusion that VPNs can't be blocked.
> Good day to you sir
And a very good day to you too.