There are a number of things going on with regards to this issue, tax policy in general and your argument.

1. There's a difference between using the tax code legitimately as written to avoid taxes versus pushing the envelope and attempting to manipulate the code then following that with extensive legal challenges to avoid even having those manipulations reviewed

2. The tax code itself is ludicrous if it can allow a billionaire to avoid taxes at all- that's a Congressional problem

3. Trump has been documented looking for loans using his stated value on property at a high dollar level, then stating the value on his taxes at a far lower value- that's fraud.

4. It's not about double entry accounting. It's about the risk of debt coming due to a man with his finger on the nuclear button! No low level intelligence agent could get away with that- #SecurityRisk! It is documented Trump's relationship with oligarchs and DeutscheBank are fraught. In addition even Trump's son said they were getting financing from Russia.