There are two issues with that. Potentially three though I don't support the third.
1)The companies have colluded with each other to remove both him and others at the same time. This is illegal. The bans within seconds of each other of some people I follow across twitter, Facebook, and Youtube showed they were very much in discussions with each other before they even decided who to ban and also shows it didn't matter as much as to what specifically they were banning people for.
2)Companies are colluding in regards to the speech of political opponents. A company heavily involved with the government receiving tax breaks no one else in San Fransisco gets is removing one sides political speech. Coincidentally they removed the speech of the side that generally is against special tax breaks that only big tech gets. I would also be upset if a restaurant said lefties can't eat there.
3)I don't really follow this reasoning yet, but there is an argument that since a few big companies are now involved in controlling most speech since no one gathers in public squares/coffee shops to exchange ideas anymore freedom of speech needs to be applied in this regard as if it was a government entity. Once again I don't like that at all as I believe companies should be able to do what they want. But, it is a valid argument.
Also the main point of this was asking if Trump had incited violence in the first place. I looked. I watched his video where he said "Go peacefully" three times. I am still wanting proof that he was trying to incite violence.