I hate to bring up my own experience since it will just be anecdotal but I, for one, have benefited tremendously from mentorship. I am the only pure mathematician I know from Indonesia (I recently found out that Karim Adiprasito is of half-Indonesian descent, which is exciting!) and I remember, when I was younger, trying to find some sort of mentorship/advice/precedent from someone from my area of the world about pursuing a career in mathematics.
While I feel like I have now easily "camouflaged" into my corner of mathematics, I recall being uncomfortable, if not, "out of the water" around …