I think a lot of 90s skits gave the album a cinematic feel, expanded a theme or told a story like 'Ready To Die', 'OB4CL' or 'Mr Hood'.
As time went on through the 2000s, a lot of rappers seemed to throw skits on just because it seemed like the thing to do, but they didn't add anything to the listening experience.
I mean besides songs Wu-Tang threw movie dialogue, bonus beats/non rap music snippets, grimy scenes, airing out beef with other rappers etc. Theres nothing that I would skip, but you can also blame them for later rappers doing it for no good reason.