You're right that debanking shouldn't be allowed; but the solution should be legislation that bans or heavily regulates debanking across the board, not executive fiat that specifically protects the president's friends and allies.
I otherwise applaud your commitment to the rule of law.
If politics is a risk to stability (I know at least one fortune 100 finance company that does have it in their risk register) then this Trump executive order against de-banking is aligns with the former one from the Obama administration.
A defense against de-banking is a bi-partisan win.