Actual legal scholars have done deep into this issue and the arguments against it are pretty bombproof but they're over 120 characters so you won't read them.
Here is the legal opinion of a constitutional lawyer who hates Trump and originally believed the Fourteenth did apply but subsequently changed his mind because technically the President of the United States is not an officer due to being elected while officers are appointed.
Trump is loathsome, but because of a technicality in the drafting of the Disqualification Clause of Section 3 of the Fourteenth Amendment, the Clause does not apply to Trump. The Disqualification Clause applies to four categories of people who have previously taken an oath to uphold the Constitution and have given "aid or comfort" to an "insurrection": 1) officers of the United States; 2) members of Congress; 3) members of state legislatures; and 4) state "executive or judicial officers." On January 6, 2021, Trump was obviously not: 1) a member of Congress; 2) a member of a state legislature; or 3) a state executive or judicial official. That leaves only the question of whether former President Trump was "an officer of the United States."
This is a harder question than it may appear because the term "officer of the United States" seems colloquially to apply to the president. The presidency is an "office," and former president George Washington called himself an officer of the United States. The Senate in debating Section 3 of the 14th Amendment was of the view that the president is an officer of the United States. In my foolish youth, I once argued mistakenly in print that the President is an "Officer of the United States." Thirty-three years of academic research and writing on the presidency has persuaded me that the words "officer of the United States" are a legal term of art, which does not apply to the President.
The Commission Clause of Article II, Section 3 imposes a duty on the President: "he "shall" i.e. must "Commission all the Officers of the United States." This is done by the President signing a document called a commission formally appointing executive and judicial branch officials to their offices. No President has ever, either before or after, the ratification of the Fourteenth Amendment commissioned himself. Why? Because the President is not technically "an officer of the United States."… Forty-six Presidents of the United States have construed the Commissions Clause as not obligating them to commission themselves because presidents are not technically "officers of the United States" all of whom are appointed not elected. (emphasis Calabresi’s)
Which brings us to the Appointments Clause of Article II: "[The President] shall nominate, and by and with the Advice and Consent of the Senate, shall appoint Ambassadors, other public Ministers and Consuls, Judges of the supreme Court, and all other Officers of the United States, whose Appointments are not herein otherwise provided for, and which shall be established by Law:". Here again the phrase: "Officer of the United States" is used to describe appointed persons and not elected persons like the Members of Congress or the President. The Appointments Clause thus bolsters the implication of the Commissions Clause. Presidents are not, technically, Officers of the United States" as that phrase is used as a legal term of art in the Constitution. (emphasis again Calabresi’s)
Finally, consider Article II, Section 4. It provides that "The President, Vice President and all civil Officers of the United States, shall be removed from Office on Impeachment for, and Conviction of, Treason, Bribery, or other high Crimes and Misdemeanors." Note that the President and Vice President are mentioned –alone and separately from – "all civil Officers of the United States." That is in part to make clear that the President is impeachable, unlike the King of Great Britain, but it is also because the President and Vice President being elected like Members of Congress, are not technically "Officers of the United States."