It's not a 'projectile', but instead a 'beam of energy', but JeremyECrawford's definition of a projectile is extremely limited and wouldn't describe any version of EB, so that doesn't prove much.

Does your idea of a 'Crackling beam streaking' toward a target fit this description? It can't hit objects or anyone but the target creature. However you imagine your EB looking and sounding, it makes sense to account for the fact that it can ONLY affect the life force of a creature.Traditionally, a projectile is a thing shot from or thrown as a weapon. It isn't a 'projectile' because it's not shot from a Some spells are drawn to or harm only the life force of creatures. or how do you justify this with specifies creature - always assumed it disrupted life force via force The definition of force damage, not of force itself, is 'pure magical energy focused into a damaging form' (PH, 196) This thread of tweets by the game's designers about Eldritch Blast has a lot of interesting information that is relevant to this question, if not directly answering it (since they also say we can imagine it how we want): Designers: It's force and damage can't target objects, only Sage Advice says EldritchBlast&similar can't cast on objects at all.

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