HCT are cheap, reliable, and simple. Even those considering transistor solutions would be advised to look instead at HCT family ICs just for simple interfacing. Even a single channel interface made using transistors is larger in circuit board space, more complex to build, and likely to cost more - especially so if you put a value on time. Fault finding with HCT is ridiculously simple, whereas a transistor format has multiple points for potential faults, and will take much longer to fault find, and to replace a faulty component. "Keep it simple" usually pays well in the long run!!