They lost market share years ago. That ship sailed and it isn't coming back. Strong market share enabled them to innovate. Their current strategy as you pointed out suits them and they are doing very well with it.
btw, I could take your argument and say there has been no real innovation in the entire bike industry in 80 years, only incremental improvements.
That's an excellent point on the loss of sales and it's effect on research and development. Of course, officially Camapagnolo wound deny a slump in either.
Granted, innovation is a subjective term and you can make arguments for and against any invention. It all depends on where you personally draw the line. However, IMO, since the mid-1980s the innovations from other companies have generally been more significant and have had larger market impact than Campagnolo.