For a start its a strawman argument, as 'scotland' in the terms you mean doesnt exist at Westminster. And even if it did, hownwould scotlands will be represented better? Thete are numerous views in scotland, places of wealth, deprivation, industry, finance, urban, rural.
It gets to the heart of the SNPs conceit that they think they speak for Scotland. They dont, dont even speak for a majority of MSPs.
But scottish MPs, ergo Scottish voters have clearly had influence. Whether or not it has had enough influence, is obviously a moot point. But to say it has always had next to zero is clearly wrong.
The tories thread has a discussiob aboit how scottish MPs helped bring down a labour government in 1979. Quite influential, no?
There have been numerous Scottish PMs, cabinet members, some very influential thinkers.
The creation of the labour party was heavily influenced by Scots. Id say that was quite important.
The West Lothian Question, named after a scottish MP represrnting a scottish constituency.
And in my lifetime, two scots have led the lib dems, and two have led the labour party (three if you count tony blair). Alastair Campbell is scottish, as are many commentators, journalists and others in and around Westminster.
And of course there are 56 SNP MPs who are doing a sterling job of holding the UK govt to account, arent they?