Engineers like to work from the bottom up because nature isn't made out of straight lines and regularity. Breaking things apart into abstractions works to a certain point, then the natural irregularity of reality steps in and you need to be able to react to that and adjust your foundation. So yes, fundamentally it is about thermodynamic knock-on-effects of handling things from the top-down.
Messing around with lisp and smalltalk environments is fun. But the moment you have to stick your hand beneath the surface, you can very quickly end up in someone else's overengineering hell. Most serious GNU Emacs users shudder at the thought of hitting Doom Emacs with a wrench until it suits their tastes. It's universally agreed that building your Emacs environment up from the defaults is fundamentally a wiser choice. Now realize that a full Lisp operating system is several orders of magnitude more complex than Doom Emacs, and most things you're going to program emacs to do are absolutely trivial in comparison to most industrial-grade application logic.
Messing around with lisp and smalltalk environments is fun. But the moment you have to stick your hand beneath the surface, you can very quickly end up in someone else's overengineering hell. Most serious GNU Emacs users shudder at the thought of hitting Doom Emacs with a wrench until it suits their tastes. It's universally agreed that building your Emacs environment up from the defaults is fundamentally a wiser choice. Now realize that a full Lisp operating system is several orders of magnitude more complex than Doom Emacs, and most things you're going to program emacs to do are absolutely trivial in comparison to most industrial-grade application logic.