http://www.bbc.co.uk/news/business-21047652
The 'high street' is certainly changing its size/shape/face.
The Internet/digital is making a big difference. On-line shops are selling things cheaper than 'real' shops. Fewer people have been buying cameras because they have 'good enough' photo taking options on their smartphones.
Seems unlikely that Halfords or Evans will disappear - but nothing can be certain anymore!
Local bike shops will survive on service(s) - fast/competent bike fixing, 'take it home NOW', decent advice etc.