because, even if they don't get the higher level spells til far too late, there are still a plethora of useful low-level utility spells that don't need to scale from upcasting: alarm, bane/bless, charm person, healing word, comprehend languages, detect magic, disguise self, entangle, faerie fire, feather fall, find familiar, fog cloud, goodberry, identify, jump, mage armour, speak with animals, unseen servant, all those just from 1st level (even if from across several spell lists but with more magical secrets that myself and many others included that's a moot point), those are the sorts of things perfect for the jack of all trades utility and support class that many see the bard as.