I think you are wrong in the first part of your sentence. It is not true that 'You get one chance to build the neural pathways that guide you for the rest of your life'. There is a great deal of plasticity in the human brain, or no one would be able to learn new skills or a new language in adulthood (yes, learning a new language in adulthood is often more difficult than in childhood, but plenty of people do it); no one would be able to adapt to changes in the world over time; no one would parent differently from the way that they have been parented. Yes, it's best if children don't begin life with bad habits that they will have to unlearn; but that's not the same as 'If you don't learn X as a young kid, you never will' - there are very few things where that is the case. If young people find that their behaviours are resulting in friendlessness or employment difficulties, and if the behaviours are simply the result of learning bad habits, they can usually learn to modify them.
Also I think that there is a difference between 'gentle parenting', permissiveness, and being the 'centre of a parent's universe'. Almost all babies and extremely young children are to some degree the centre of their parent's universe, and vice versa. Usually they partially detach from one another to varying degrees as the kid gets older. And it doesn't necessarily entail permissiveness, Some of the most over-permissive parents whom I've encountered have been people who've found it easiest to ignore their children and let them do as they please so long as they keep out of the way; and some of the strictest have been people who did regard their children as the centre of their universe, and this included moulding them into a very specific shape.
Gentle parenting is not the same as permissiveness or lack of parenting, though I suppose it can sometimes be used as an excuse for it.
What probably is true is that a mismatch, in either direction, between level of aggressiveness in parent and child may make parenting more difficult. A naturally aggressive, even if loving, parent may intimidate a gentle child; and a gentle parent -whether on principle or by nature- may find it very difficult to understand and to discipline an aggressive child.