Although they all tired of it quickly, the New Glasgow Boys label applied to Steven Campbell, Ken Currie, Peter Howson and Adrian Wiszniewski was more than a useful marketing tool.

Of the same generation and GSA training, all four were figurative artists with a gift for the fabulous, whether dark or light. Exhibited together in the 1980s, they made coherent sense – especially to untrained eyes – in a way that, say, the YBAs of Goldsmiths did not.

Thirty years on from their graduation, the four are rarely spoken of in the same breath. Campbell, whose work was arguably the most complex, died five years ago. Currie is painting more luminously than ever, shows at Flowers gallery in London and his Three Oncologists is one of the gems of the reopened Scottish National Portrait Gallery. Wiszniewski had a successful exhibition at London's Albemarle gallery last year and Scottish shows at Glasgow Print Studio and the Robert Burns Birthplace Museum, and is something of the renaissance man with his writing and musical theatre projects.

Howson is even more – but less purposefully – ubiquitous, his work rarely far from media attention, whether dealing with national pride (Burns), celebrity culture (Madonna), or contemporary faith (Christ), but the clarity and dignity he brought to his early pugilists, neds and jakies is gone. Now his work has been chosen to replace Salvador Dali's Christ of St John in Glasgow's St Mungo Museum of Religious Life and Art.

This is the latest chapter in a sorry saga. Ian Begg's 1990 building was designed with the much-loved Dali as part of its interior and was pretty much a tribute to Tom Honeyman's inspired acquisition of it for the city. When it was moved to Kelvingrove Art Gallery and Museum (where it is much less well displayed), it left a silly gap. Until recently that was filled by a Craigie Aitchison, which had the justification of being inspired by the Dali. Now that has gone and Howson's Crucifixion, 2010 has taken its place. The work is an insult to the art that has gone before it (and particularly to Aitchison) and completely out-classed by the small Belgian carved Madonna and Child from Sir William Burrell's collection that sits beside it. I have heard eloquent discussion about the meaning of Dali's painting, but this work says nothing at all and the artist's inane statement on the wall alongside says nothing for it. Glasgow's hard-won status as a hot-bed of the visual arts is immeasurably diminished by its display.