> Pretty sure that was a point early in his presidency where he was block, but Twitter being a US company was not allow to block the US president....?

IIRC, there was a lawsuit that ruled that the president was not allowed to block other twitter users. As far as I know, it would still be totally withing twitter's right to block Trump, if it wanted. But I think they don't because what he says on Twitter reveals important information about his character.