> President isn't CEO
The President is literally the Chief Executive officer in the United States.
https://people.howstuffworks.com/president4.htm
> Laws and budgets are set by Congress
That's correct, under Article 1, but the President does not have to spend every dime that was allocated.
> EOs do not have the force of law
"Both executive orders and proclamations have the force of law, much like regulations issued by federal agencies"
https://www.americanbar.org/groups/public_education/publicat...
You seem to underestimate the power that is vested in the office of the President as the Chief Executive.
> have been invalidated by courts
As have many, many legislatively-passed laws; this is simply checks-and-balances and allows the judiciary to act on other laws (which originate from Congress) and regulations (which originate from the Executive Branch).
Chief Executive officer does not mean dictator other than to military agencies. Please read the history of the bipartisan creation of the civil service, of the Administrative Procedures act, all created bipartisanly to reinforce that the President is not a dictator/king.
The executive has discretion in how funds are disbursed, but they have to fulfill all the obligations laid out by Congress. Impoundment is expressly illegal, not just due to Article 1, but also the Impoundment Act to avoid any ambiguity. The Dept of Education, for example, is created by act of congress and has a list of obligations in the congressional budget and the president has no authority to deny that. They have discretion in terms of how it is fulfilled and who gets paid when, but they are assuredly not allowed to just cancel programs or agencies that explicitly funded by congress.