Jean led one team for eleven issues against one opponent, and getting help from the Avengers to boot. Afterwards, she suffered one of the worst defeats the X-men ever had in Disassembled. Havok has a better track record than she does.
That requires you to ignore Uncanny X-force, because every single decision Logan made there, without exception, turned out to be a failure that came back to haunt him and the team. Also, the fact he didn't do much leadership at all in WatXM, just letting other people do his job for him while he was avenging/fighting ninjas/getting booze.
Also, ignores the fact that Scott lost more students, but he unquestionably and undeniably saved more lives, including Logan's, many, many times. It's like saying a general with dozens of battles under his his belt is worse than another one that only commanded a few because the latter lost less men.
Also, Storm has been shown to be resentful of Scott quite a few times, and slept with Logan both before and after Schism, so her opinion is hardly proof of anything.
Basically, your opinion only works if you ignore 56 years of X-men history to focus on Schism, and even then that would make it very debatable.