I think it’s a matter of perspective: If one thinks the mekubal is in power to get things done, that is wrong. (The same goes for any Tzaddik.) If one goes with the mindset that this Mekubal or Tzadik is on a higher Madraigah and therefore has more Ruach Hakodesh than oneself, so he can give (better) advice and his davening can have a greater effect because of the greater mass of Zechusim he has.
Unfortunately, I think that some people have the former mindset which borders on Avodah Zarah.
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