No, the problem with the joke is that it doesn't just make fun of her, it also uses the fact that she is a woman and mother to make that joke. This plays into sexism and misogyny by implying that both of these things made her unfit for office by default. Note how the "sanitized" version using fingers instead of children doesn't really have any oomph to it - the sexism is not just window dressing, it's what makes the joke work.
Jokes are not "just jokes". Jokes play off culture and reinforce or challenge it. People having a low number of fingers doesn't do either of those things so at that point it stops being a joke and becomes a dry empirical claim ("they have at most ten working aircraft"). Stand up comedy is an art form and takes considerable effort, creativity and repetition. Dismissing jokes as "just jokes" as if they are shallow brain farts is like saying poetry is "just words". Jokes are worth analysing and being dissected just like any other artform and even if they're genuinely created by "amateurs" they're informed by the culture that surrounds them.
VdL is a terrible politician, I strongly oppose her value system and I think she does indeed have a history of failure. But that's not how the jokes are framed, that's merely the setup to the jokes. The jokes wouldn't work with a male politician because the punchline is that she's a woman and mother.
You can agree with the punchline but denying that it's sexist or misogynist (in the sense of "women and mothers are unfit as politicians") is silly even if you don't like those labels being applied to your sense of humor. Jokes are inherently political because culture is political. It's why reactionaries will say progressives aren't funny and why progressives will roll their eyes at jokes about trans people and say "that's just the one joke".
Clever comedians will actually use this and drop off-color jokes on audiences in the middle of a show to reveal their own hidden biases when they "accidentally" laugh about a joke they'd normally claim to be appalled by. But there's a fine line between doing that to lampshade dishonesty and just telling those jokes. And even then it requires a cooperative audience. As an example you can look at Chris Rock who felt he had to retire his routines that used the n-word because it emboldened racists rather than making fun of them.
