Just to put my two pennyworth - I’ll try to be brief here but happy to post supporting links if anyone is interested.
Firstly, the RD 07/2018 is shown as in effect on the BOE with Article 3 (2) being the basis for publicly funded health care for permanent residents (although you have to do a bit of work to get there). Furthermore, this is confirmed on both the UK Goverment and European Commission web sites which state directly that permanent residents are elligible for publicly funded healthcare.
Secondly as other posters have said, nobody has come on the forum to confirm they have been able to get health care through this route. It’s the same story on other forums and Facebook pages. However what's also interesting is that the INSS are simply refusing to process their applications either dismissing them from the office or putting the paperwork onto an eternal pending pile. Normally, once the initial document check is completed, the application would be processed and the legal basis for any rejection communicated in writing. This was confirmed by my local office. If permanent residents didn’t qualify then I’d expect an organisation as bureaucratic as the INSS to simply process and reject.
Here's what what I think may be happening. One of the provisions of the RD 07/2018 transferred the direct responsibility for checking the eligibility to the right to public health care from the INSS to the Ministry of Health. In contrast to the RD 1192/2012 which not only gave the INSS legal responsibility but also outlined some rules, for example, regarding an appeals process. The re-assigment of responsibility may not have mattered if the Ministry of Health had provided the supporting regulations to the INSS instructing it how to process new applications under the RD 07/2018. However, according to INSS website, it is still waiting on the Government. Here's a link to the relevant text in the Management and Control section;
HOME. Apartados y Secciones destacables del portal web.
www.seg-social.es
So without a new rule book, the INSS simply continues to apply the one it already has. (For example, the form for in person applications is still the one from 2012). However, it can’t reject applications from permanent residents since it does not have any legal basis for doing so (the RD 2018 anulled most of RD 2012), neither can it approve them without the new regulations. So It pretends the applications simply don’t exist. This is entirely consistent with the posts from people who have tried to apply down this route
Since the INSS continues to work to the pre-existing processes most people will not see a difference. There’s no change either for foreign citizens whose countries have a social security arrangement with Spain. And, of course, the key beneficiaries of the RD 2018, los sin papeles, have their applications processed by the Autonomous Communties rather than the INSS
So I would guess UK citizens (and maybe USA, Australia etc?) are disproportionately affected. The other clear beneficiary of RD 2018 would be those with an income of over 100,000 euros pa. Probably not the groups foremost in the Governments scale of priorities.
Finally, the long awaited el Proyecto de Ley de Universalidad del Sistema Nacional de Salud (SNS) has started it’s legislative journey. It contains the same provision regarding permanent residents as the RD 2018. If it ever gets into the BOE, It might be worth applying again.