LD games were all CAV (30mins, 36min PAL) because CLV wasn't intended or useful for interactive/gaming use. (The LD-V8000 made CLV workable for it, but not until 1989 or so)
So LD games will 'only' take 100-110GB, and the 10-bit data compresses well because there are 6 bits which are always 0. And if it really became a concern a packed 3x10->32 bit framing could be done, it just hasn't been done yet. There are advantages for the dev phase for working in signed 16bit.