Not debating the rest but you can’t say that Eisenhower did not have executive experience.
Executive experience does not exclusively refer to governors. Executives exist outside of civilian government.
I do believe that being a five star general in charge of the European theater of WW II qualifies as executive experience. I believe Washington and Grant also had executive experience.
But certainly some Presidents with executive experience did not do so well. Former governor Carter could have done with some real world experience outside of government.