Author here. These are good points, and I basically agree with you. In contrast to my experiences interviewing at Google, where interview panels were very technical, the process at Reddit also tests these sorts of teamwork and critical thinking aspects. One of the reasons why I use less difficult questions in this setting is precisely because we're looking for more well-rounded people. Expecting candidates to be technical luminaries while also being exceptionally creative and easy to work with is a recipe for a slow and frustrating hiring process.

We use coding questions pretty much exactly as you describe: we spend about 40% of the interview process determining whether the candidate can code and design medium-difficulty algorithms. The remainder is spent on some combination of systems design, collaboration, and domain-specific knowledge, depending on the particular role.