Legitimacy of electoral systems vs illegitimate and vicious government policies

Dude Swheatie has just signed a Make Votes Matter petition letter Minister for Constitutional Affairs John Penrose. This is in support of a change: 

1. from a 'first past the post' electoral system 
2. to a Proportional Representation (PR) system.(1)

Dude Swheatie has added this message to support his signature:

Under a 'first past the post' electoral system, the economic clout of campaign funders — even those who are non-UK citizens — dominates over the interests of the most vulnerable in our society.

How many of those who voted against proportional representation know of the extent and viciousness of what U. Glasgow law professor Dr David Webster 'Britain's secret penal system'?(2)

I believe that Proportional Representation would help bring about far more legitimate government in the UK.

Link

1. https://www.change.org/p/david-cameron-reform-our-voting-system-to-make-it-fair-and-representative-makeseatsmatchvotes/u/16905545
2. https://www.crimeandjustice.org.uk/resources/benefit-sanctions-britains-secret-penal-system