A brief history of Dutch style kickboxing and what makes it an unique style:
In the second half of the XX century Japanese martial arts instructors have adapted Muay Thai techniques into Kyoukushin karate and called it a Japanese Kickboxing. A few fighters from Netherlands traveled to Japan to learn this new style and then in the late 70's they have established a new gym in Amsterdam where Dutch school kickboxing was created. Kickboxing gained a lot of traction in Netherlands in the 80's and it started to be very popular since then.
Dutch kickboxing relies on powerful Western style boxing combined with a heavy low kicks. It also makes use of a head kicks and knee strikes but a very few elbows strikes are learned cause training focuses on K1 and Glory competitions mostly and those rules forbid elbow strikes. It also doesn't make much use of teeps or clinch fighting. Despite this disadvantage the best Dutch fighters could face native Thai champions and win those fights thanks to a heavy, more technically sophisticated boxing and an aggressive style of fighting. Boxing combinations are also used to set up headkicks and heavy kicks to the body.
Muay Thai doesn't have such a good boxing techniques due to a different scoring system which rewards kicks, elbows and knee strikes much more than punches. But it holds an advantage when it comes to utilizing elbows and clinch fighting (Dutch style does have clinch fighting techniques but they are less sophisticated). Thai Boxing also has another powerful weapon in its arsenal - a teep - for which Dutch style kickboxers don't have any good answer. Another thing that is different is a stance - kickboxing stance is more boxing oriented, better adjusted to a heavy swings and left+right+left+right strike combinations. Also, Dutch fighter put more pressure o footwork and they generally move around more and strike from a different angles.
Andy Souwer vs Buakaw Por Pramuk K1 World Max fight. This is a good example showing Dutch Kickboxing versus Muay Thai in action:
Muay Thai vs
Dutch style kickboxing