Nothing wrong with video support on any iPad, including the iPad Pro.
I use both Videoshop AND LumaFusion on iOS and those video apps have been working wonderful for me and many others who edit video on an iPad.
I edit video from my iPads, iPod Touch and my digital cameras both on iOS and on my Mac and have not had any notable major issues with doing so on either platform.
Been editing videos shot from my iDevices using my iPad Pro for the last two years.
Like I previously stated, I have no idea why YOU had issues with importing your videos or doing video editing on the iPad ( you never explained how the import was done or what the original source material was shot with), but your issues are not everyone’s issues,
If you were having so much difficulty with using a third party video editor, these third party video apps have help forums of their own on the video editor developers’ websites.
In addition plenty of video tutorials online on YouTube for many popular apps and for popular iOS video editors.
You had access to other online resources to help you learn how to edit video on an iPad.
I repeat, once again, the iPad Pro for you was a missed/wasted opportunity.
The tools for the iPad Pro are out there and they work. And many of the more “Pro” level apps for iPad work brilliantly!
The iPad Pro for me has been nothing but a positive, powerful, creative device for me and many others!