If you are creating professional video, you want the best video editing computer you can buy! As you move into higher resolutions and more complex editing you'll notice that your PC takes considerably longer to prepare your clips. Other factors such as file type, codec and resolution all impact the speed you can edit, playback, render and export your finished project.
All of these tasks put heavy workloads on your CPU and GPU, the best strategy for optimal performance is choosing a balanced approach to GPU and CPU decisions because video performance tends to be limited by the lowest performer of the two.
Luckily, the application you use for video editing won't have much impact on your processor decision, they all tend to have the same hardware requirements.
Processor clock speed is an important performance factor. The core count is also important, the more cores you have the faster your processing performance. We typically don't see the benefits of more processing cores tail off until you have more than 10 cores and even then the tail off is gradual. However, some processors with high core counts will operate at a lower clock speed which can have some impact on performance.
The final thing to consider should be the number of PCIe lanes and maximum memory supported by the processor. This can be a limiting factor for people working in higher resolutions.