Longer answer: The court case surrounding Trump's twitter account was incredibly narrowly scoped - it was specifically about the communication happening via @realDonaldTrump and nothing else. The court determined that Trump used it as a way to, as the president, directly and personally communicate with constituents, and that those specific circumstances were why he couldn't block people from that handle.
Whether or not the White House youtube page falls under the same classification of direct communication is honestly probably a question worth asking. If someone challenged it in court, the decision over Trump's twitter would almost certainly be brought up to argue that they shouldn't be allowed to block commenters. The court could determine that the same rules apply, or the court could say that this youtube account is a general information channel that is not a direct line of communication from an individual holding office to constituents and therefore falls under a separate classification. There's also always the possibility that legislation could be passed to more firmly establish these rules.
Short answer: maybe
Longer answer: The court case surrounding Trump's twitter account was incredibly narrowly scoped - it was specifically about the communication happening via @realDonaldTrump and nothing else. The court determined that Trump used it as a way to, as the president, directly and personally communicate with constituents, and that those specific circumstances were why he couldn't block people from that handle.
Whether or not the White House youtube page falls under the same classification of direct communication is honestly probably a question worth asking. If someone challenged it in court, the decision over Trump's twitter would almost certainly be brought up to argue that they shouldn't be allowed to block commenters. The court could determine that the same rules apply, or the court could say that this youtube account is a general information channel that is not a direct line of communication from an individual holding office to constituents and therefore falls under a separate classification. There's also always the possibility that legislation could be passed to more firmly establish these rules.