What’s the benefit? Are humans, in general, incapable of meeting a deadline that isn’t physically enforced? The zcashd internal wallet is going away, and we’re not going to delay that for a year. The community doesn’t want us to delay it for a year, and also, you can’t make us continue to maintain C++ code! (Tongue only slightly in cheek.) And therefore, any Sprout support after NU7 would be unusable, because even folks like @hanh who want to talk about hypothetical Sprout-supporting wallets other than the zcashd internal wallet, don’t actually want to implement one.