For me, the answer is no. I feel it is likely that future architectures will also have vulnerabilities that will eventually be discovered and require subsequent (software) mitigations that will probably negatively impact performance to some extent. Further, as it may take several years or longer to address this from a hardware level (possibly 2, 3, or 4 generations after 8th gen wafers?), I don't personally think waiting is justifiable if reduced productivity is a consequence. As of right now, I have applied the mitigations on my Kaby Lake devices, but am not using them on my Haswell device as, to my understanding, the performance toll is more significant (similarly, I am using the iOS update with the mitigation on my X, where I am not on my 6s.) YMMV.