Actually the 25th Amendment has gone into effect with little fanfare when the President has a medical procedure that requires him to be unconscious. The Vice President becomes Acting President for a few hours. When the President is restored to proper awareness papers are signed returning the office to the President.
Nobody seems to notice that the 25th amendment does not foresee actually removing a President from office. If it was successfully invoked, the Vice President would become Acting President, but the ostensibly incapacitated President would still be President. Even if the anti-Trump members of Congress were to vote by a two-third margin in both Houses that Trump was incapacitated, he would still be President.