> If Leetcode is all you can think of to do to learn and practice skills then you've got a poor imagination.

I think the point is that real-world experience often doesn't translate into Leetcode skills, meaning that you have no choice but to devote time to the otherwise-useless[0] skill of solving Leetcode problems. If making a cool side project, etc. was what helped most software developers get better at interviews, "people here" wouldn't be complaining in the first place.

Sure, you are learning something by solving Leetcode problems, but not anything useful[1] except in the artificial world of software interviews.

[0] This is probably heavily dependent on the specific jobs in question—I'm only speaking from my personal experience.

[1] Same as [0].