I gave you the link where the CRS released their report(post #296)... as to if a President can shut down the border or not with an EO..
I went to the report you quoted and here is what it actually says: "
While the executive branch has substantially restricted alien entry pursuant to authorities triggered by a declared public health emergency, the extent to which the executive branch may rely on generally applicable immigration statutes to restrict or suspend entry on an equally broad scale remains untested. Federal statutes grant DHS general authority over operations to secure the border and specific authority to temporarily close “any ... port of entry” when necessary to protect national interests.
The courts were challenging Trump all the time because they had already become a part of the Deep State. They did not want Trump to succeed.
But did you ask yourself if would be absolutely in the national interest of the USA to shut down that border completely?
Now let's be really honest. Has Mexico been waging war asymmetrically (indirectly) against the USA for a very long time? Is the flooding of the country will illegals, illicit drugs, drug traffickers, human traffickers, etc not a form of warfare? What about the war of the Mexican cartels at the same time? What about national security and the free entry of terrorists into America? If anyone would be TOTALLY HONEST the answer would be
"Shut down that border until Mexico takes full responsibility. Or wage total war against Mexico and the cartels until there is a satisfactory resolution. " Mexico would make sure this was only "temporarily" because it depends on trading with the USA.
America wants to wage a prolonged proxy war against Russia to presumably "protect" Ukraine's border, but the Feds will do absolutely nothing about their own border. How do you explain that?