I will speak for the SJs because that is what I feel most capable of arguing for.
Because Si is about preserving what one knows, it is often mistaken as pure "tradition" from the era in which MBTI was created (not sure of the exact year, but I think it was the 50s). So we have the submissive homemaker who lives to please. But that isn't how young people today are, generally. Nobody identifies with that. So, with a superficial knowledge of type theory, they steer clear of that typing. I can speculate that this might be a reason we don't see many SJs, especially ESxJs, on the internet. Because they all think they're something else.
This is also why everyone thinks their annoying great-aunt is an SFJ. SFJs are the only ones who can be homemakers and NPs are the only ones who can be oddball revolutionaries. Honestly, though--whose great-aunt is going to wear Converse and flower crowns? Whose 50-year-old mother is going to take black & white pictures of herself with mascara running down her face? Nobody's. Using stereotypes, it's nearly impossible for anyone over a certain age to be anything but SJ. I bet there are plenty of INFP grandmothers who stereotype as ESFJs, and plenty of ESFJ youth who stereotype as INFPs.
I am very personally annoyed by this stereotyping because my type tends to get the worst rap. Seriously. Nobody wants to be an ESFJ. Because they're always boring, unoriginal, always happy, and always confident. The truth of the matter is that everybody feels different and weird. Everybody feels hurt and alone at some point. So they all scramble for INFP and INFJ because those are the only types "allowed" to feel that way. It's very sad.
I kind of rambled here. In essence, stereotypes are misleading and almost sure ways for mistyping.