Leaving aside the whole tone of 'Aliens made them into bugs', it all falls apart for me when he says "it's no longer a twisted manifestation of sexual fear". I don't see how Covenant changed anything. It's been speculated forever that Alien could've been engineered, and David even taps into this by telling Oram the huggers are waiting for "mother", and his possible 'sexual awakening' by kissing David, and then more passionately kissing Daniels.
Plus there's the tired and dull old chestnut about how the Alien is entirely Giger's doing and not "Dan O'Brannon" (SIC) or anyone else.
And HR Giger was Giger's professional name - it wasn't colloquial.