You're comparing an average, but the demographics are different. If you compare, say, native-born-white to native-born-white, they fit those inputs much closer.

Total fertility is down because a smaller fraction of the population are immigrants from Mexico and Central/South America now and those immigrants have a higher birth rate. Their children regress to the mean.

I don't follow.

The fertility rate has decreased significantly for US-born women of every race and ethnicity since the 1990s. I couldn't quickly find good stats on trend in birth control usage or labor force participation by race, ethnicity, or immigration status, but I'm skeptical that the trend is in the opposite direction for any particular demographic.

So I expect the claims in my previous comment still hold even for, e.g., native-born whites as a subgroup: flat-to-decreasing birth control usage, declining labor force participation, but still declining fertility rate. Obviously the magnitudes of those changes may be different at the subgroup level, but I don't see how the data is compatible with the claims of the comment I initially replied to.