I would consider medicine to be a subset of Science, and finance to be at least related to Math (with some disciplines being very heavy math.)
STEM as a whole is basically the entire top half of that chart. Even math, which you call "pretty weak", is (taking the average) as close to CS as it is to communications, and much closer to the top cluster than it is to the bottom cluster.
So I think "study STEM" is perfectly good advice, particularly given that there will be shifts in the value of various degrees based on subtle economic changes.
STEM as a whole is basically the entire top half of that chart. Even math, which you call "pretty weak", is (taking the average) as close to CS as it is to communications, and much closer to the top cluster than it is to the bottom cluster.
So I think "study STEM" is perfectly good advice, particularly given that there will be shifts in the value of various degrees based on subtle economic changes.