Then the disagreement is that I would still call that lying. If someone knows the truth but says something contrary to that truth, it is lying.
The problem seems to be that Trump is not good at knowing what is necessarily useful. He just seems to lie reflexively, without putting any thought into it.
What he seems to instinctively rely on are two things: that the bolder the lie, the more people will believe, and that you should say what your target audience wants to hear, so they’ll come up with the excuses for you. He also noticed that a new lie (especially a larger one) can distract from an precious lie.
He does not seem to ever actually think about his lies. But, if he knows that what he’s saying is not the truth, but says it anyways, that is a lie. Many lies are made by instinct and no thought.
A better liar would be able to do all Trump does, but also be able to think about which lie would be the most convincing or least likely to get them into trouble. Trump generally hasn’t gotten in trouble for his lies, and has always tended to lie to people who were I a less powerful position than him, and thus their disbelief did not hamper his goals.
He did seem to learn a bit about how to avoid legal liability from his lawsuits, but only in a specific context of never saying exactly what he wants the other person to do for him (like a Mafia boss). He didn’t learn more complex stuff because he’s always been able to steamroll over others with brazenness and money. Heck, with more powerful opposition, even not directly saying things might not be enough. He’s no longer a merely a rich businessman who our capitalist system is too reluctant to pubish.
If he were smarter, he’d figure out the change in circumstances and make changes, not go entirely on instinct.
But, regardless of how much thought he puts into it, I would still call it lying.