Blockchain is ok for maintaining data integrity of electronic data. AI is good for applications with branch decision making capabilities. One area the two technologies could eventually overlap is in the realm of security.

A blockchain might be utilized to maintain the data integrity and codebase of an IT security product. While AI might be utilized in the decision making aspect of the security app. This isn't necessarily a likely scenario. Operating systems already include measures for maintaining runtime integrity. AI also isn't necessarily reliable or predictable enough to reliably be granted admin permissions atm. But it is possible someday we may see the evolution if progress and advancement occurs.

Another possible scenario is AI codebase eventually becoming integrated and standardized in many traditional apps and assuming a natural role in systems which currently utilize blockchains.

Personally I doubt we'll see AI included in sectors where gains in the technology are negligible and may not provide value in terms of risk versus reward. There are thousands of different scenarios in many areas people wish AI to fill. Pattern recognition in AI may not scale sufficiently to accurately respond to all those thousands of different circumstances. Which could lead to them not being preferred.