Why is this Teflon Don tweet stupid?
Run-on sentences and improper use of capital lettering, make Trump appear totally uneducated. X {x} marks the grammatical and spelling mistakes.

realDonaldTrump: Never has the press been more inaccurate, unfair or corrupt! We are not fighting the Democrats,{x} they are easy,{x} we are fighting the seriously dishonest and unhinged {x}Lamestream {x}Media. They have gone totally CRAZY. MAKE AMERICA GREAT AGAIN!
6:07 AM · Aug 10, 2019

https://twitter.com/realDonaldTrump/status/1160160760179372032

Trump tells O'Rourke to 'be quiet' in wake of El Paso shooting
BY BRANDON CONRADIS - 08/07/19 12:13 AM EDT

President Trump late Tuesday night responded to criticism from former Rep. Beto O'Rourke (D-Texas), who has repeatedly assailed the president following a mass shooting in El Paso, Texas.

"Beto (phony name to indicate Hispanic heritage) O’Rourke, who is embarrassed by my last visit to the Great State of Texas, where I trounced him, and is now even more embarrassed by polling at 1% in the Democrat Primary, should respect the victims & law enforcement — & be quiet!" Trump tweeted.

In response to Trump's tweet, O'Rourke said, "22 people in my hometown are dead after an act of terror inspired by your racism. El Paso will not be quiet and neither will I." https://thehill.com/homenews/administration/456479-trump-tells-orourke-he-should-be-quiet-in-wake-of-el-paso-shooting

As for mocking people, because of their given names:

Donald Trump's ancestors changed their surname from "Drumpf" to "Trump."

Donald’s grandfather was a German immigrant named Frederick Drumpf who emigrated to the U.S. in 1885 and became a naturalized citizen in 1892.

At some point, he started calling himself “Frederick Trump,” but it is unclear if he ever changed his name officially. Some have speculated that he didn’t want to be known as “Drumpf” because of prevailing prejudice against Germans (which would heighten, of course, during World War I). https://www.snopes.com/fact-check/donald-drumpf/