This is not necessarily true. One easy way to compare version N and N+1 is "how much work (test time compute) does N+1 need to do to match the previous capabilities of N". It is true that some domains are currently hard to verify (e.g. biology is more difficult than math), but this is less of an N vs N+1 issue and more of a data domain issue.

How is being faster equating to more intelligent . Speed can achieved in a lot of ways for lot of tasks, a simple lookup table can fasten most algorithms but that doesn’t make them “smarter”.