At its core is better "selling skills" In my last job I noticed how much better people that did jobs like waitressing before were more likeable by Clients. Small things like saying at the end "John thanks for your time..." Put the name first, people like that. But in the end you might have done well and failed you on salary requirements...
Depends on the user. Basic LaTeX2e/LuaTeX can be learned over 5 days. Guru level like any programming language needs its 10K hours. There are people who have an aversion for backlashes. The main reason for the "\" is perhaps the only char that is not commonly found in texts. Others like ":" re very common in texts. When parsing LaTeX and behind it is Knuth's original TeX engine, the commands are swimming in a sea of text (as the Dragon book says).