The fit and cut looks very similar to the PT era Kenobi to me, accounting for 50 year Ewan not having the exact same build as 20 years ago.
It's actually really confusing for me with his long hair. In long shots, quick action shots or out of focus, he looks way too much like AOTC Kenobi. I keep doing double takes. It's very confusing.
While I get the idea of long shaggy hair makes sense for Ben hiding in the dessert, I don't think it was a wise choice given the character's history and character progression as reflected in his styling and costuming from AOTC through ANH.
I mean this would have been a great opportunity to give him a more OT style belt as he cobbles together makeshift adventuring gear. Or at least add some grey to Ewan's hair to make him look more Alec Guinness-y and less like AOTC Obi-Wan!