  Electronic nematicity is often found in unconventional superconductors,
suggesting its relevance for electronic pairing. In the strongly hole-doped
iron-based superconductors, the symmetry channel and strength of the nematic
fluctuations, as well as the possible presence of long-range nematic order,
remain controversial. Here, we address these questions using transport
measurements under elastic strain. By decomposing the strain response into the
appropriate symmetry channels, we demonstrate the emergence of a giant in-plane
symmetric contribution, associated with the growth of both strong electronic
correlations and the sensitivity of these correlations to strain. We find
weakened remnants of the nematic fluctuations that are present at optimal
doping, but no change in the symmetry channel of nematic fluctuations with hole
doping. Furthermore, we find no evidence for a nematic-ordered state in the
AFe$_2$As$_2$(A = K, Rb, Cs) superconductors. These results revise the current
understanding of nematicity in hole-doped iron-based superconductors.
