There were three reasons for the downfall of NDS/Cisco SPVSS.
Pay-TV landscape change: the income generated by classical broadcast industry started to change with the rising of internet streaming. NDS was not prepared for that enough nor it could adapt culturally to the lower profit margin created by OTT and DRM.
NDS becoming a private company: anyone who saw from inside saw that many bad decision were made in NDS during the time it returned to be a private company. Since there were no serious oversight and no investor vision some of the top managers could afford growing such fat in the company which couldn't be handled later.
Cisco acquisition: Cisco killed the well oiled sales organization which NDS had during on-boarding, no wonder sales were down. This together with 1. and 2. plus that video was far from Cisco-s main business caused complete irrelevancy within the enterprise despite the obvious talent.
Had not one of these three happened NDS/Cisco SPVSS would still be around for a long time.
I'm not mad at Cisco, though I pity them for not being able to be a true tech company.