I half agree and half disagree.
I’m assuming that by architecture you’re referring to system/enterprise architecture and not eg CPU architecture. For a given system, the viable solution space is massive, and the decision on which approach to use is a mixture of science (analyzing and meeting numerically-defined requirements), art (meeting soft requirements), politics (making everyone happy about the unquantifiable choices), and taste (choosing between different similar solutions when no other constraints makes one better than the other). Two organizations facing the exact same problem can come up with two vastly different solutions that both effectively solve the same problem.
How those decisions get made is, I believe, an extraordinarily interesting social sciences question!
There are huge seats of computer science that do, to me, fall under the umbrella of “hard science”, but not all of it. Philosophy, taste, and social dynamics play a huge role in “industrial computer engineering”, and to try to pretend that’s not the case is setting ourselves up for failure.