Well, I'm going to take a pile of heat for this, but if they wanted some realism on a T-Shirt, they could show a row of ride vehicles from Horizons with maybe 2 out of 10 with any riders on it.
Sadly, not unlike the current incarnation of Journey into the Imagination, Horizons was sadly under appreciated in the end and grossly under attended and had to be replaced. No, I'm not commenting on what has replaced it as it's nothing visionary like Horizons was, but to pretend that these long lost rides were so epic, so enlightening and so enjoyable that they were a must see for each and every visitor to the parks just does not appear to be supported by reality. Like Mermaid today, they were all walk ons in the end. Had Compaq, now HP not invested in Mission:Space, we'd probably be discussing the two side by side shuttered attractions in WOL and Horizons, because it wasn't generating any worthy interest at all. I too miss the attraction, as I miss Cranium Command and more, but it needed thousands of more passengers by its gate than it was getting.