It is kind of funny, that we seek meaning and/or purpose in everything - our lives, our actions, our thoughts - but there is a nice change in perspective in considering it as something that we produce rather than find.
Any species that has this trait must not get stuck in local maximums, at an extreme that's why the koala is just not a resilient species, over confidence.
We are an anti-niche species, to avoid this we must have a certain percentage of our population that has doubt, existential crisis that shakes us out of a well worn path.
This always amazes me. If you deeply, emotionally _know_ that life has meaning, there will be some existential nights where you you will think "but maybe life doesn't have meaning", and if you _know_ life is meaningless you will sometime find yourself thinking "maybe there is meaning", our brains try to keep us from getting stuck.
Humility in the face of the unknown. As a species, just amazing stuff.
The cycle of confidence and doubt is absolutely amazing, it's kept us from getting stuck.
Keeps us from having "target fixation" and lawn darting into the ground.
Some individuals have these values tuned at extreme ends, the full distribution is represented by humanity.
The most overconfident and the most anxiety ridden, this is all in our spectrum, and it turns out better or worse for each individual.
The great thing is that we can share ideas and examine our priors.
I used to believe that "nothing" was a real thing, but it's only an abstraction, nothing has never been observed it's only "real" in our imaginations. There's no such thing as nothing as far as anyone has observed or proven.
Same thing with meaninglessness, nothing is meaningless, there are just bits of meaning maximally un-complex and decohered. You can use photon emissions from stars for RNG, humans have made even RNG have rich meaning and high practical utility.
This gets tricky because our perceptions can be influenced by societal expectations of which things should be meaningful - as if it's an objective property. It's easy to think of activities to which many people would respond "Oh, that must be soooo meaningful" and yet it's entirely possible you may not personally experience a sense of meaning from doing them - yet feel like you're supposed to. It's important to realize there's nothing wrong with that (or with you). You may not experience the 'expected meaning' meaning while doing some "charitably noble activity" widely thought to be meaningful, yet discover something else few would associate with "meaningful" does evoke meaning for you.
Why does intrinsic meaning make this advice not useful? I have always understood this sort of advice to mean “do things that are meaningful to you”.
Inevitably you have to compromise on what is the most meaningful thing to achieve some reasonably happy balance. How much compromise, how you internalize it to yourself, etc. you have to figure out.