Look up the Flynn effect. You're right in the first paragraph, but wrong about the direction.

The Flynn effect ended several years ago and started reversing.

Even if that turns out to be true, rather than it starting to hit a ceiling where we can expect it to not consistently go in a single direction it does not alter anything I wrote, which addressed a comparison between 1956 and 2026.

The claim of a "lack of intelligence in modern times" is flat out contradicted by the data. It'd take a lot of regression to get back to 1956 levels.