SRAM Force is worth the upgrade if you're a competitive racer or serious rider who wants pro-level performance with a bit more refinement than Rival offers. You get the same wireless eTap AXS shifting platform, but Force is lighter and has noticeably crisper ergonomics that matter during long races or intense training sessions.
The big differentiator for Force is power meter integration. If you're training with power—a must for structured racing programs—Force makes adding a power meter seamless and clean. Rival can do this too, but Force's power meter options are more integrated and lighter.
For most recreational riders, Rival delivers nearly the same wireless shifting experience at a lower price. Force makes the most sense when you're building a no-compromise race bike, you're already committed to the SRAM ecosystem, or you want that power meter integration without stepping up to Red's premium price tag.