The Diablo GM stated in a recent interview that we’re not going to find many legendaries until after level 25.
The criticism is completely valid. Your character shouldn’t be decked out in legendaries by level 20. You shouldn’t have your entire build set in stone a fifth of the way into leveling, or even a significant portion of it. This really shouldn’t be a controversial criticism.
D3 is great, but one of the worst things it ever did was make Legendaries rain from the sky and the D4 team have been very transparent about wanting to avoid that in D4.