The UK isn't in Schengen so it's not part of this. They're not putting visas up (or don't intend to) for Canadians or Americans. There's a bit of a bromance going on for the anglophone countries.
Romania and Bulgaria aren't in Schengen, either. This isn't a Schengen issue, this is a European Union issue.
The UK on the other hand has no intention to join and don't intend to put visas in. This issue is more a Schengen than an EU issue.
It has to be this way because when you enter the EU it is either Schengen or the CTA (UK/Ireland).
While technically Bulgaria and Romania are not yet in Schengen, they have to enter at a future time.
The Swiss, Norway and Icelandic visa policy IS involved because they also have to fill in the silly form and pay the fee to visit the US/Canada as part of the Visa Waiver Program or eTA but a US/Canada citizen can simply enter Switzerland or Norway (Schengen) without any forms or fees.
While Bulgaria, Poland and Romania have the WVP issue this isn't the only reason for these measures. This is on the agenda too (how they are not in the WVP) with the USA despite intending on being in Schengen.
While the UK/Ireland also has the ETA these negotiations don't have anything to do with it as they will not be imposing Visas on US or Canadian citizens.
The visa policy of the Schengen Area is set by the European Union and applies to the Schengen Area and to other EU member states without the opt-outs enjoyed by Ireland and the UK
https://en.wikipedia.org/wiki/Visa_policy_of_the_Schengen_Ar... https://en.wikipedia.org/wiki/Visa_policy_of_the_United_King...
And that is exactly why it is a Schengen issue. The Schengen agreement contains more than just the passport free travel area. It also contains transitional rules for the countries that are obliged to join the passport free area like Romania and Bulgaria.
I think the misunderstanding results from the fact that the Schengen agreement is now part of the EU treaties. So yes it does affect the whole of the EU apart from the countries that have an opt-out (UK and Ireland)
Schengen == "there are no passport controls at border crossings"
Visa Waiver Program == "you do not need to apply for a visa in the destination country's embassy"
While you have numbed it down it is simply that the Visa Waiver Program is tough on Romania and Bulgaria and also has a fee for the ETA whereas there is no such thing to go to the Schengen area from Canada or the USA.
So yes it does have to do with Schengen, but not the treaty specifically as it doesn't involve inter EU travel.
It is a bromance considering what you need to visit Australia as a non anglophone country.
China is Australia's largest trading partner (both imports and exports) but they have it nothing like the anglophone countries. Even on the tourism front there are more Chinese tourists than Americans, but its still not easy..
In fairness the only reason a 'Visa' is required is because its reciprocal.
The EU has near no requirements for Australians (you can just get in) so they have the free eVisitor whereas the US needs an ETA (not really a Visa) but its pretty much reciprocal to the Visa Waiver Program in terms of the online application and fee.
That being said there's something even more special to anglophone countries having the Queen as the head of state in terms of the visas (including the working holiday kind)
Speaking of Indonesia, they even charge you to leave!
The EU doesn't have any of this, you just get in and get on with your day.
Unfortunately because the bastion of freedom charges a $14 fee and makes you fill in a very visa like form the EU may soon have this blasted visa form too :/