Technology

Trump believes that all executive branch employees are directly reportable to him

Sort of, he believes they should be, not that they are. He wants to replace merit-based positions with appointments, which means he can more easily replace them as needed.

When he implements his tariffs for example, and other countries retaliate with their own, the value of American goods will plummet

The value of American goods is irrelevant. We're not a net exporter, and our most valuable trade partners (Canada, Mexico, EU) would likely get exceptions.

Tariffs would hurt imports and result in more purchases of local goods, which increases demand for labor while decreasing purchasing power (i.e. inflation), but then we'd respond with higher borrowing rates, which decreases labor demand and fewer total purchases of goods, etc. The short-term impact is a spike in labor demand, but the longer term impact is slower growth. It's a bad policy, but it's not so inflationary that the dollar would lose value, the average American would just become worse off. We need the dollar to be stable because we need it to remain the main international reserve currency, and we're absolutely willing to let the average consumer suffer to keep that status.

Simply blocking those payments could tank the currency

I guess he could theoretically veto a budget, but Congress would likely pass it anyway. He doesn't have that much control over his own party, and doing that would piss off voters enough that they'd likely lose in the midterms. It's not going to happen, the fight over the debt ceiling is for concessions, and politicians will concede to prevent default.

if there’s no legal consequences

There has pretty much never been legal consequences for the President, the only thing the Supreme Court decision does is say the quiet part out loud. We'll put on a show for things like Clinton's affair or whatever, but not for anything of consequence. The law is scary, but Presidents have largely been immune from legal consequences for pretty much the entire history of the US.