Very good at manipulation and bribery though, which is ironic because he's also very easy manipulated and bribed.
I am not sure he has ever been good at those things, either.
He has certainly had people—mostly fixers, attorneys, and contacts within organised crime—that were quite good at manipulation, intimidation, extortion, bribery, and blackmail. But he has very rarely ever been the one do any of it.
And he got setup with those people initially through his father, and then later through a series of connections and associations from that early arrangement. It was a chain of associates that intimidated, extorted, strong armed, bribed, and blackmailed the associates (and business partners) that came before.
His three true gifts are: self-promotion, grifting, and having absolutely no scruples.
He has always been good at those things. And that has helped him get out of quite a few massive holes he dug for himself over the course of his life, at various moments of near ruin. Mostly his personal brand and his willingness to do whatever is necessary (and I do mean literally whatever) has allowed him to stay afloat all this time, even as he squandered millions—perhaps billions—pumped in to his businesses.
Mary Trump has talked and written at length about those attributes allowing him to get where he is today, and how many people in the family saw (and see) him as a person that just kept failing up, with no discernible talent apart from being a sociopath that was exceedingly good at creating and maintaining the false persona, at any cost, we all know so well now.
That is ultimately why he is so easily manipulated and bribed: he is actually incredibly predictable. All you have to do is appeal to his personal brand—or threaten it—and you have power over him. You can very reliable forecast how he will respond to basically any provocation or suggestion.
He is the ultimate puppet: dumb but insatiably ambitious.
And now he is more desperate than he has every been before.