I wouldn't trust American perspectives,
Try the original UK ones then

Money is already draining from Britain but because of Corbyn, not ...
https://www.spectator.co.uk › Features Dec 1, 2018

A Labour government is unambiguously bad for markets': Experts ...
https://www.investmentweek.co.uk/...week/.../fund-buyers-corbyn-next-election-labou...Jan 3, 2018

The economic consequences of Jeremy Corbyn | Financial Times
https://www.ft.com/content/0e956c1e-a8e5-11e7-93c5-648314d2c72c
Oct 5, 2017

How might Jeremy Corbyn and a Labour government affect ...
https://www.marketviews.com/.../how-might-jeremy-corbyn-and-a-labour-government...Jan 9, 2018

I can understand your reluctance to accept the above unanimous conclusions PM Corbyn would be a tragedy and a disaster of epic proportions. SCARY!
The more "challenged may see it all as propaganda but I suspect that respected publications such as the Financial Times have a wee bit more nous about such things than contributors here.
Labour of course is but a byword for fiscal irresponsibility.