I strongly agree with this point. Most of day-to-day problems in software engineering / craftsmanship (i.e. the work most people are paid for in this industry)

I strongly agree with this point. Most of day-to-day problems in software engineering / craftsmanship (i.e. the work most people are paid for in this industry) are not computer science problems, they are about the process of understanding your user requirements, iteratively improving your product, achieving and maintaining the appropriate level of quality, and the meta-cognitive skills around identifying when you just need need to fix a bug vs. step back and look for a way to improve your tools. You will get some transitive learning of some of these things if you do lots of coding challenges, but I personally found a huge benefit in my formative years from building a single full-stack application over many months, much more than solving simpler day- or week-long standalone tasks.