Turns out the use more pay more model already exists in Europe, Both Spain and France have such tariffs. Dont know about other countries.Because, for low usage households, it represents a significant proportion of the bill.
At the start of the year, my total bill (gas and elec) was £33/month. The SC element represented around 12.5% of that bill (£4.20)
Now my standing charge is £25/month and represents 25% of my bill. ¼ of my bill is standing charges.
By the same calculation, that would represent around 8% of your bill so perhaps this might help you realise why low users are particularly aggrieved by it.
I could boohoo your annoyance at the large increase in your bill - you should reduce your usage then as it's your fault your bill is so high but I don't as I realise some households use that amount (bigger house, less efficient house, more occupants etc).
It is correct that the increase is on units. It would be hard to justify another large increase in SC given supply costs haven't risen much
Just because something seems trivial to you doesn't mean it's not trivial to someone else.
If we fully utilised the benefits of smart meters here then we would see the same benefits.
France adjusts the SC based on usage, Spain adjusts the unit rate.