I think it's simplistic to say they've won because 'the war' is ongoing - they have lost things they considered to be invaluable (safe havens, sympathetic/blind-eye states, funding, any kind of long standing, senior leadership) and have been pushed out of a number of temporal territories with astonishing losses of fighters and commanders.
They now spend far more time managing/attempting to manage their own security than they do prosecuting their wars. That is very different to how they were operating in the summer of 2001.
We haven't won - we're still conducting counter IS/others ops in Iraq and Syria, we've been supporting the French op in Mali for years with airlift, helicopters, and UAV's, we're sending a very crunchy battlegroup to the UN operation in Mali because of IS's success in the Sahel - but they've not won either: safe havens are hard to find, they are beset with enemies, the fear and effect of penetration agents has had, and continues to have, a toxic and paralysing impact on morale and effectiveness, and any leaders that appear have a terrifyingly short life expectancy which causes huge organisational and political churn, paralysis and infighting.