Note that you said high rise. A 2 story building with half dedicated to retail has too much retail in general (in some specific situations it might make sense, but if every building did that there simply isn't enough need for retail space). However a 100 story building with only one floor retail needs more retail space to satisfy the residents' needs.
That also depends on the location. In a residential neighborhood, that might be too much retail, but in Times Square it might be appropriate. There are walkable low-rise neighborhoods in Queens where the main drag is all 1-3 story buildings with retail in the ground (and sometimes second) floor and sometimes apartments above the retail. Meanwhile, around the corner are entire all-residential blocks. This works and is still walkable because getting from all-residential to retail is just a quick walk around the corner.
Agreed, which is why cities should ensure a certain level of population density around retail.