Well, "throw your leg over the middle bar" certainly would be more difficult with a higher bar. However "throw your leg over the middle bar" falls into the "complete idiot" category. IMO, of course.

FWIW, I'm personally among those people who ride frames "much too large" for me. Or, put another way, I ride frames that were considered appropriately sized 40 years ago, when big frames were "in". I do it because I prefer riding long distances in relative comfort. If I decided to go criterium racing, I'd be on a smaller bike...

IMO, the LeMond/Hinault/Guimard/Renault sizing method (one example can be found on the Colorado Cyclist website) is pretty good at getting folks into a reasonable size. It was popularized in the 1980s when we were getting away from the "French fit/fistful of seatpost" method that results in really big frames, but hadn't yet gotten to the "monkey humping a football" method that results in today's really tiny frames.

HTH!