I think there are two elements to Fowler:
The first is more personal, and fueled by the kind of negative suggestions and implications that this forum thrives on - is he only here because he's Karl's mate; is he only here because Tiger owes him something; is he only here to plug his academy into a club; is that at the expense of our own young talent; etc,etc
The second though is a more pragmatic view - is he going to actually be any good as a manager? His spells managing abroad have not been bursting with success stories; he hasn't been able to secure a gig in the UK, despite his profile; his academy and other business interests may impact upon his time and focus;
I think some posters are focusing heavily on the first element, perhaps overly so (who knows whether any of these have any truth in them?), BUT I still think the second element probably contains enough concerns for him to rank well below some of the other contenders, so don't think he represent the ultimate wow appointment to get the fanbase rocking again