I think there are several reasons why their sales could have suffered but everybody’s needs differ.
When I was looking around 2019/20 the Stage 6 I test rode was brilliant. Light, lively, nimble and really well balanced. They were one of the first to balance longer reaches with proper length chainstays.
On the flip side, they’ve since gone too far imo making overly long bikes that are too speed focussed and lack some of the qualities I liked.
They also seem to have been playing catch-up on useful features like the bottle mounts (important for me like many others) and bike storage. Coming late to market with something really quite.ugly and of unnecessary complexity that would have been better served by a second set of mounts and made to measure storage bag.
Still somewhat regret not getting that Stage 6 though.
Here’s hoping they are able to continue operating, I think the sport would be poorer for their absence.