Why does this narrative "core branches are not for females' exist?

So I am planning to switch to mech/civil from ece and one thing I am hearing is, apparently core has no job for girls 🫩🫩

It's total bullshit I know that but will probably get judged by society ( who cares)

But why does it even exist

https://redd.it/1x6o7mm
@BTechtardsReddit