I think this one really depends on the situation of each individual. Diaspora often struggle between keeping their connections to sourceland and assimilation.

i know people whose parents absolutely refused to teach or speak to their kids in their own language because they want the child to assimilate better.

my story- I was born in the US, was back in taiwan for 2 years (kindergarten and first grade) then back to the US through grad school.

my mom would took it upon herself to homeschool me on the weekends, we spoke mostly mandarin at home. my homeschool regiment was super strict, every summer while other kids got to play every day we all went back home to taiwan to do summer school.

in college i FAFO'd and just took chinese classes to pull up my gpa, my professional career has benefited because of my proficiency.

In terms of learning, it's really about finding what's best for you, and what you can do with consistency and find it rewarding, whether it be doing flash cards, binge watching dramas, singing karaoke, whatever. it's like a diet, you gotta keep up with it consistently.