I don't think this is fair. When Corbyn first got elected to the leadership, he said he wanted to involve talent from all wings of the party. But remember how it took him days to assemble his first shadow cabinet? That's because all the competent New Labour people refused his approaches and strode off to snipe from the back benches. All he could get to join him was lefties and second-rate chancers. A shame and a missed opportunity for Labour. With a shadow cabinet of all the talents, things could have gone very differently despite Corbyn's management limitations.
Corbyn started off with a decent shadow cabinet,many resigned after Benn was sacked.
Resignations
On Sunday 26 June and Monday 27 June 2016, a number of members of the shadow cabinet either resigned or were sacked. This process began with Jeremy Corbyn sacking Hilary Benn as Shadow Foreign Secretary in the early hours of Sunday morning after Corbyn informed Benn that he knew Benn had been constructing a coup against the Leadership during the run up to the vote to leave the European Union. Subsequently, the following resigned (in chronological order):
Heidi Alexander – Shadow Health Secretary[12][13][14]
Gloria De Piero – Shadow Minister for Young People and Voter Registration[13][14]
Ian Murray – Shadow Scottish Secretary[13][14]
Lilian Greenwood – Shadow Transport Secretary[13][14]
Lucy Powell – Shadow Education Secretary[13][14]
Kerry McCarthy – Shadow Environment Secretary[13][14]
Seema Malhotra – Shadow Chief Secretary to the Treasury[13][14]
Vernon Coaker – Shadow Northern Ireland Secretary[13][14]
Charles Falconer – Shadow Justice Secretary[13][14]
Karl Turner – Shadow Attorney General[13][14]
Chris Bryant – Shadow Leader of the House of Commons[13][14]
Diana Johnson – Shadow Foreign and Commonwealth Minister[14]
On 27 June:
Lisa Nandy – Shadow Energy Secretary[13][14]
Owen Smith – Shadow Work and Pensions Secretary[13][14]
Angela Eagle – Shadow First Secretary of State and Shadow Business Secretary[13][14]
John Healey – Shadow Minister for Housing and Planning[13][14]
Nia Griffith – Shadow Welsh Secretary[13][14]
Maria Eagle – Shadow Culture Secretary[13][14]
Kate Green – Shadow Minister for Women and Equalities[13][14]
Luciana Berger – Shadow Minister for Mental Health[13][14]
On 29 June:
Pat Glass – new Shadow Education Secretary[14]