I agree cash is likely to be less and less of an issue going forward. That said I have checked with one of my EV owning pals and he confirms that he still has to have several apps and RFID cards if going further afield.
Some companies - BP for one - are going down the credit/debit card route but others - like Ecotricity who have a virtual monopoly on the motorway network, do not allow universal access.
I can only go on the ones near me, and all the sites within ten miles are freely accessible without subscription or pre-registration, except for one - which is one of the hosted units on a small filling station. I live near the A1, and there are very no Ecotricity sites around here at all, Shell & BP seem to be the most common trunk road/motorway sites within 50 miles or so.
This really isn't rocket science. Incidentally, by 2030, research indicates that the fuel mix of cars on UK roads will be 12 million EVs and 21 million ICE (some hybrid of course). Ideally you would want those numbers reversing. Anecdotal evidence (my neighbour owns a garage) indicates that resistance to going EV will last long after 2030 until and unless universal access and universal charging protocols are adopted.
2030 will still see a lot of legacy vehicles on the road, people like me aren't going to be rushing to scrap perfectly good petrol and diesel vehicles. I think we will also see residuals of these vehicles plummeting soon, that's why I have absolutely no intention of ploughing any sort of money into a car for some time. It's a tricky time to be buying. Petrol/diesel is on the way out, and electric is still in the early adopter phase really, without fully matured technology.
I think things will soon change as the big fuel suppliers switch over to recharging sites, and the common standards for charging are already in the pipeline. I think your garage owning neighbour will be surprised by the progress over the next 5 years, and I suspect that there are many drivers of diesel/petrol cars who don't realise how quickly this infrastructure is being built.
I agree progress is being made. My argument is that it is not happening quickly enough and, as far as I can see, no progress has been made towards a universal charging protocol so ALL cars can recharge at ALL charging points.
A universal charging standard is coming, many of the volume manufacturers have signed up to the project, and even Tesla have committed to it.
Really interesting discussion this though!