The arches on those CL shoes do look very steep - unless the heel is indeed higher than 130mm (surely not?). It is also set back too much for real elegance (imho), although the sheer height does make it a pretty attractive shoe.
As to walkability, the girl in the video seems to manage quite well and is probably 'practised' rather than 'professional'. Obviously, some people (regardless of sex, age, weight etc) find 5"+ heels quite easy to wear; others have difficulty. Some 20 years ago, I had a girlfriend who was very willing to wear high heels when with me; she was about 42/43, not petite, size 7UK feet, and neither an athlete nor a dancer (actually a nursing assistant). Although she liked heels, I doubt that she was used to anything higher than about 3.5" when I met her. She was soon wearing 4.5" stilettos regularly (notably the neat Faith 'Tina' courts) and, to my surprise and pleasure, was both willing and able to go higher, not that much was then readily available. We went shoe-shopping in London for her birthday and she liked the patent slingbacks with a full 5.5" heel that I bought her from Honour at Waterloo, and found them quite easy to walk in after just a little practice - but avoiding steep slopes etc as one would expect! Her heels were noticed when we went out - the typical reactions (usually unspoken) being 'how on earth ...?' or 'slut' - the latter being very unfair as her appearance otherwise was always neat and fairly conservative. Alas, the relationship did not last and I have never had one with a 'real heel' wearer since.