I always wondered why the base human sub race exist when the variant one is in all cases superior. Am I missing something there or is 5e really broken on that aspect?
This was one of the mis-steps from older editions into 5e, imo. Humans used to get different bonuses that were very beneficial in the older editions, ASI freedom, extra feat at level 1 (in addition to the normal feat at level 1 that everyone got), extra skill points, and favoured class freedom. This meant that while human was not the best choice for some extra-specialised builds, they were very good at being flexible and could be turned into nearly anything without any kind of significant penalty.
And then all those penalties were taken away. Skill points turned into proficiencies, and favoured class was removed as a concept. So WotC replaced that flexibility with extra stats, which is not a bad choice, but it made human feel comparatively weaker than any other PHB race, and removed what was supposed to be the specialty of humans, their flexibility. Variant human put back some of the flexibility.
