As other's have written already, ß is not simply a ligature. Since the orthography reform in the nineties it universally indicates that the preceding vowel is l

As other's have written already, ß is not simply a ligature. Since the orthography reform in the nineties it universally indicates that the preceding vowel is lengthened, dropping it would lead to a large amount of homophones. An example is Maße (measures) vs Masse (mass).