I think there will be a shake-up in retail soon.
There will be a few good, higher end (but not 'designer') brands selling quality items that people expect to last, and cheaper 'fast fashion' for the young who want to change their look more often and for those who can't afford the better things. The rich will continue to spend thousands on clothes, shoes and bags as always, but the current 'mass market' will either move one way or the other, or will lose out.
I predict that Next, White Stuff and similar will struggle to hold market share, as their things are not well made and are pricey for what they are. Shops like Hobbs, Reiss and LK Bennett will probably manage but with lower profits, and Peacocks, H&M etc will continue to sell to the younger/cheaper market.
Clarks will probably broaden its appeal as it seeks decent shoes to a wide range of markets, and other stores will have to do the same to survive.