Amrûnril
Hero
Where WotC made the wrong call was in setting the benchmark of your primary stat at level 1 at 16 - as is shown by every single pregen having a 16 in their primary stat at level 1. They then made it physically impossible to reach that 16 when using the standard array with any race that didn't have a bonus in their primary or secondary stat. And not being able to reach the benchmarks just feels bad. This means that thanks to what is in this particular spot the poor design of the 5e PHB playing anything other than a cookie cutter race/class combination just felt bad.
This meant that in PHB 5e most races can not meet the benchmark in the majority of classes. This was exceptionally bad for table diversity. There was a really awkward patch for this by creating a plethora of subraces for 5e - but this grew messy. And for a (non human/helf) race that doesn't have subraces you can't meet the benchmark in four out of six stats.
I'd go a step further and say that the issue isn't just the benchmark, but more broadly the focus on "primary ability scores". If a fighter with 14 strength and 14 intelligence could have similar combat effectiveness to a fighter with 18 strength and 10 intelligence, this would be an entirely different conversation.