IT IS what the majority of people voted for, so it very much IS a valid argument. If you don't like it, tough luck, but that's how democracy works. You can vote next time to change it.
Any alterations that overrule the will of the majority, makes it not a democracy anymore, and you don't want that since that opens a can of worms that can always be used to also override your decision next time.
Which is why the world is never going to view or deal with the US the same way they did before. The current administration and its actions represent the will of the American people; represents their world view, their desires.
Also, the President is not a King, so just because people voted for him it doesn't mean opposition ceases to exist. Opposition and push-back to executive policy been a mainstay of US politics. It's been true of Democratic Presidents (e.g., federal courts blocking Biden's policies), and it remains true of the current President.
If you look at the approval rating for democrats and republicans, as reported by CNN this week, that disagrees with you. People who voted for Trump seem to be happy with what he's doing.
https://www.natesilver.net/p/trump-approval-ratings-nate-sil...