On the pedantic side, it’s straight, I thought cat 5 pairs were meant to be twisted? Other worry for me would be, it looks kinda fragile. And by definition, it’s going to be laid around doors, under carpets, precisely the places that a mechanically robust solution is needed.
Then again, I am prepared to believe that a few inches untwisted makes no odds. And performance-wise it must surely beat WiFi or home plugs.
Bottm line though, if a person wants decent data around the house, and understands why WiFi and homeplugs cannot ever be relied upon, wouldn’t they just drill a hole in the door frames & skirting boards for a proper Cat 5 cable?