I wouldn’t say node is the thing, it’s just easiest to learn.
But every company has their own stack.
Node is used a lot as a bridge language, but most corporarations use Java/c# on the backend.
Facebook uses PHP
Airbnb uses Ruby
GitHub uses Ruby
Bank of America uses Python
Bitbucket uses Python
PayPal uses Node
Netflix I think is Ruby, I don’t remember. Might be node.
You aren’t going to be the perfect fit for every company. Just depends their stack related to your skills.
I`m not a Dev so the Stack doesn't matter but I do find it beneficial to have technical skills.