The CR-21 was a private effort to create a new rifle for the South African military in the 1990s. Bullpup designs were all the rage at the time (Austria has the AUG, France had the FAMAS, the UK had the SA80, etc), and so a company called Lyttelton Engineering Works (now part of Denel Land Systems) created a bullpup conversion design for the South African R4 (Galil). It was given a very fluid, futuristic look, and equipped with a fiber optic optic without any iron sights. The action and magazines remained original R4/Galil, however
Most service rifles have triggers that recreational shooters would consider bad compared to available aftermarket options. Sure AR-15s can have very nice aftermarket triggers installed, but as an example, USGI M16A4 triggers were not very good.
Fine tuned triggers are not a major consideration for military service rifle adoption. If a bullpup is being primarily designed as a service rifle, the ability to fine tune the trigger is similarly not a primary factor in design.