I began my answer with "Yes and No". What you're describing is the "yes" - they can both be an early step in a long D&D journey, taking up the same place in a D&D journey.I don't at all think he was saying that they were having the older-gamer's experience. He was saying, that these have the same position in their experience, as the older modules do for older players. Saying they are analogous is not suggesting they are exactly the same experience.
The "No" is what I described - that these are fundamentally and radically different journeys. They share the name of D&D, but they are such different things that taking your earliest steps on each of these paths is fundamentally different in the ways that I described. The "older-gamer's experience" is inherently part of what made Demonweb what it was, and that experience is not part of what Storm King's Thunder is.
So, superficially, yes. But when we look at whether they are actually the same type of experience in a way that allows us to say they serve the same function - not as much.