Great tips on what can definitely be a frustrating topic... I'm about 12 yrs into playing - having started from absolute zero at age 42 (zero = I can't ever even remember *holding* a guitar before that). I have fingers that drive me CRAZY bc of their shape - not really fat throughout but they are very meaty on the pad (where your fingerprint is)... this has been the path to madness of unwanted muting of adjacent strings on "stretchier" open chords...but I learned, as I slowly progressed, that almost everything on guitar is some sort of trade off... once I started playing barre chords and quickly changing from a single string to laying a finger down to form a mini-barre when playing single note lines etc., that thing that was (and is still for certain things) such a liability is actually advantageous... so yeah - keep going, you got this, you'll eventually sort things out !
When playing really trickychords, I’ve also found it sometimes helps to slide my thumb further up or down on the back of the neck, so the angle of my hand is different. It doesn’t always work, but there’s a couple chords that I can’t play any other way.