That's a good point except there is webcam, phone and media footage that show no planes as well. Originally on youtube there were many more videos than now that showed no planes. Bit by bit over the years most of them have vanished.
At the time I was watching a news channel, I don't know which one, and turned it on just before the second plane/explosion. They went live to an American news channel with a camera on the towers. A few minutes later there was an explosion in the second tower and they referred to it as such with no mention of a plane. I certainly didn't see a large plane and they didn't either. The news feed then went back to the UK channel and next time the same footage was shown a short while later, there was the plane going in to the second tower. I was a bit confused and thought that maybe I just didn't see the plane. Now, 20 years on, I dunno. I still think had the tower been hit by a plane in the original footage I would have seen it just as the American presenters would have.
Also, there is no way of knowing if the videos that showed the planes came from genuine people or were placed on youtube by whoever wanted that shown instead of no planes. Or how many have footage showing no planes that haven't posted them on social media. It's one of those 'down the rabbit hole' type of scenarios.
I think it highly unlikely that footage showing no planes had had the planes 'removed'. Out of the two, planes added or planes removed, I would have to go with planes added. In conclusion, for me, there's no proof either way just grounds of probability that the planes were added. I could be wrong of course.