My understanding as an outsider is that astrology, tarot, etc function as a shared vocabulary and mythology to communicate about mental health and life's troubles. I think for most people the occult elements are largely aesthetic.
Throughout history people have used occult aesthetics to create a heightened experience. Sometimes that can help you commit to the process and get more out of it. (And other times con artists use it to get you to let your guard down, c'est la vie.)
Personally it's not for me, but when I got to know people who were into it, and did some readings to humor them, it made sense to me.
Yes and even among hackers. Porting doom to a microwave oven for instance.
Hugo Pratt, author of https://en.wikipedia.org/wiki/Corto_Maltese - hinted at this in one of stories about the character. Allegedly Corto met some sort of Gypsy palm reader when he was just a teen. The Gypsy checked his palm and told him his life line was short, so he would die very young. His reaction: he took out a knife and cut his own palm to make the line longer.
The latter part is usually missing when you use Tarot, Astrology etc.
There is also a desire to know "what will happen to me", but I think that divinatory magic can help even if you are 100% rational: http://www.pa-mar.net/Lifestyle/I-Ching.html
To the kind of person who wants to find a proximate cause for everything, "I didn't get the job because Jupiter is in Scorpio" is much less toxic than "I didn't get the job because the hiring committee is racist".
You are completely ignoring the primary motivation of both practices which is very much in attempting to understand yourself.
It's a shame when those who decry alternative systems do so using flawed logic.
What I am trying to say is that most people will not dig further and most importantly will not even try to put some honest work in trying to understand things in order to try to repair these.
And assuming I am right, Astrology is not really helping much, because if you are "stubborn because you are a Taurus or whatever" what are you supposed to do? What kind of corrective practices will Astrology suggest?
Please enlighten me (I am not sarcastic): in all my dealings with people who were interested in Astrology (interested beyond the most superficial interest) everybody was trying to "understand", a minority was trying to "predict". But nobody had any Astrology-based best practice to "heal" or "repair".