It is because that's literally an architectural choice which prevents you from easily moving out a module from your "monolith" to another machine on the network, and causes the bugs.
The language & memory architecture... are an architecture matter.
Yes, but not necessarily: with rust you can put stuff on the heap yet it's still ownership-checked just like the stack is scoped in other languages. Conceptually I mean.
The language & memory architecture... are an architecture matter.