Complex sentence: Although there is much to be said of the advantages of a folding boat, they are not commonplace in boating and aluminium and inflatable alternatives are far more prevalent despite some folding boats having been sold for several decades.
Split into simpler sentences: Although there is much to be said of the advantages of a folding boat, they are not commonplace in boating. Aluminium and inflatable alternatives are far more prevalent despite some folding boats having been sold for several decades.