There are different factors, considerations, rules. Of course, everyone wants to lay out the perfect PCB where all the factors are considered, all the rules obeyed etc. But you cannot do this, not in the real world. You will have to disregard some of the factors, violate some of the rules. So, chose the factors which are important to you and design your board accordingly.
For example, if you have fast signals which require impedance matching, design accordingly - use thinner prepregs between signals and reference planes - this way you can get away with thinner traces and shorter distances between traces, or better yet sandwich the signal between reference planes. But don't do that if you don't need impedance matching - rather minimize the number of plains and spread your signal layers apart as much as you can - this way you can use more more signal layers.
Or, if you expect thermal problems, create big areas of thicker copper, use lots of vias to facilitate the spread of the heat. But don't do this if the heat is not a problem. Rather save space for signals.
If you want your traces in adjacent layers to run perpendicular to each other, but you cannot really do that for some reason, evaluate the magnitude of cross-talk and figure out if your desire for perpendicular wires is reasonable, and if it is, evaluate whether it can be solved by other means, such as putting wires further apart. Don't worry if "gurus" talk or don't talk about this. The processes on your board are governed by laws of physics, not by opinions of the experts.