Arthur Crabtree wrote: Plus there's been an upturn in results since he became captain
It depends how you look at it. Stokes has never captained in Australia away, which is the clear stat killer for most England captains. He also has captained series vs Ireland and Zimbabwe at times these teams couldn't be statistically any worse. If you remove Ashes away matches from Roots record and ZIM and IRE from Stokes, their win/loss ratio is essentially the same unless you go to three decimal places after 1.5. So against teams they both captained against, they are in fact identical.
If you wanted to go more deep, you could ask in terms of priorities in test cricket what status do England have at the moment? I would personally say in order of the following priorities, England circket's health check is usually based on roughly the following.
1. Ashes performance
2. The performance against the next best side of the day - So up until the 1950s South Africa, after that the West Indies till the 90s, probably SA after that till the early 2000s, then India become the biggest team on the planet.
3. Performance in Asia away to India and Pakistan particularly. SL became relevant in Murali's career span, but only really then.
4. Expected to win all other series.
====== Under Stokes =======
1. Ashes - Do not currently hold the Ashes, and has not won a series vs them under Stokes.
2. India - Lost away 4-1, currently undecided home series with a possible draw on the cards.
3. Stokes holds no current series win against an Asian side against the two best sides.
In the history of the game, there is only one period where England did not have at least one live winning record in the case of the first two examples, using the eras defined above - in 1991 with 4 series lost to Windies and Australia. They did at the time have wins home and away against India (and also Sri Lanka).
If England lose this test, it will be the first time in history they have no last series cycle victories in last played Ashes matches, the last played 2nd most important series, and no active win's away against either of the big ticket Asian sides. 80% of those series results would have occurred under Ben Stokes.