>>45 there was never "Ada machines", because Ada was explicitly designed to target a variety of von neumann micro architectures, but there were for example Apl machines.
"lispers" talking like there's lisp machines is mostly a cargo cult, but driven by a genuine desire to escape the growing complexity of modern software. it's also perhaps an attempt to escape a certain kind of lack of control over software world: at any point in the project's life there might appear an activist or a group of activists, who, often through underhanded means, will implement some new and incompatible paradigm, which is supposedly "better", often done in the name of "security" or other such amorphous concepts.
a lisp machine is the same kind of holy grail as suckless stack. the idea is to escape the constantly changing technology landscape into your own little world, where you're in control of everything that's going on. often such attempts are about constructing an intentionally restricted, minimalist environment. so in the case of a unix head such an escape will be into suckless stack, but in the case of a lisper that escape will be into a lisp machine: it might be a "emacs all the time" approach, or it might be "running sbcl for everything". some crazy people actually try and run lisp machines in emulators, etc. i don't actually know anyone who has tried moving full time onto an actual hardware lisp machine, mostly because they are slow, finicky and unruly.