Do built-in block sharpeners actually work?

Reviewer opinion is split. BestReviews and Best Buy verified-purchase reviewers praise them as a convenience that keeps edges usable. r/sharpening and r/TrueChefKnives are skeptical — they argue built-in pull-through sharpeners remove too much steel and produce a serrated rather than a true edge. For most casual users they're "good enough"; for enthusiasts they are not a substitute for a whetstone.