I think the reason Trump had to leave the G7 meeting and return to Washington is that he is neither physically nor mentally able to work a full day, much less in the evening. He certainly is unable to be in public view for long stretches of time. His minders must be able to see when he is flagging and then whisk him away. So on top of all his deficiencies you mention above, he has the issues around his clear physical and mental decline, which seem to be accelerating.
I think the reason Trump had to leave the G7 meeting and return to Washington is that he is neither physically nor mentally able to work a full day, much less in the evening. He certainly is unable to be in public view for long stretches of time. His minders must be able to see when he is flagging and then whisk him away. So on top of all his deficiencies you mention above, he has the issues around his clear physical and mental decline, which seem to be accelerating.