I think Giant bikes are one of those brands that are recommended all over the place. I know on several bike forums I am on, they're a default recommendation in terms of value vs. performance vs. quality. Tends to lead to a lot of riders who are just getting started.
They used to be the cheapest/most accessible way to get on an aero bike. The Giant St Pauls store being bang in the middle of nodder buying territory probably did it too
They were quite common place on the crit scene aswell tbf
Looks like every other Propel?
Never seen a nice one. Always ridden by nodders.