There is a note at the bottom of the BEAMA article I linked to about certain parts of England and Wales having LV Interconnected Pairs, not a generally an issue. Which I presume is part of these projects, presumably with the local network being fed from multiple points rather than just one transformer PSCC readings are going to be very variable.

https://www.enwl.co.uk/globalassets/innovation/smart-street/smart-street-key-docs/smart-street-design-and-operation-of-lv-interconnected-networks-study.pdf

and

innovation.ukpowernetworks.co.uk/.../lv-interconnected-pairs

There is a note at the bottom of the BEAMA article I linked to about certain parts of England and Wales having LV Interconnected Pairs, not a generally an issue. Which I presume is part of these projects, presumably with the local network being fed from multiple points rather than just one transformer PSCC readings are going to be very variable.

https://www.enwl.co.uk/globalassets/innovation/smart-street/smart-street-key-docs/smart-street-design-and-operation-of-lv-interconnected-networks-study.pdf

and

innovation.ukpowernetworks.co.uk/.../lv-interconnected-pairs

That study includes some odd ideas - almost everything else we know about losses says higher voltages are better.

"Conservation voltage reduction (CVR)
Electrical equipment made for the European market, including household appliances and
lighting, is designed to operate most efficiently in the region of 220 to 230 volts. This
equipment can, however, operate adequately at voltages in the region of 200 volts. If power
is delivered at voltages higher than these optimum levels, energy is consequently wasted "

Boiling a kettle or heating a room faster is not a loss it is a saving, as is obvious by thinking about boiling it very slowly, the as then it never gets warm. A 1kW kettle is a lot slower than 1/3 of a 3kW one,  as heat is lost during the process, and a 100W kettle never boils at all. So, boiling adiabatically in a fraction of a second with megawatts would be ideal but is sadly impractical.
Anything electronic with a switch mode regulator will draw more current at lower line voltage to compensate, so the wiring losses are higher.
I do now wonder now about the rest of the thinking.

Mike