As you know having a phenyl group doesn't necessarily guarantee the material to be a liquid crystal. Usually LCPs have liquid crystal parts as well as active monomers. The other reason it is not liquid crystalline because any LC molecule should be either rod-like, disc-like (columnar), bent-core or like a nanchack. However, the best reason it is not a liquid crystal could be simply justified due to the fact that it doesn't have cloudy phase.
Main chain LCPs are mostly connected with minimum 2 atoms between the aromatic rings (e.g. with ester groups). Otherwise they are not linear. They may have longer spacer groups between the mesogenic groups.
Main chain/backbone of LCP can be very flexible ( alkyl or polysiloxane, for example), but mesogenic groups should correspond to specific requirements . No need to have spacer "....with minimum 2 atoms..." .