I don't think you can judge the life of Sims 4 by how many packs or how long it's lasted. It will last as long as the devs can make it last, there will be as many Packs as they can wrangle out of it.
Packs, after all, are so much easier to make than a new engine.
Remember "My First Pet"? Quite apart from designs that completed sets that should have been in previous packs (never mind just Cats & Dogs, the bee outfit mirrors a toddler outfit from the Toddler Game Pack, the astronaut is from the jobs pack) it consisted mainly of t-shirts, curtains, unusable wall decals and floor decals (aka rugs).