You can't be a Google engineer without thinking about scale-out. However, Google et al have a different kind of engineering than most other companies: they have tons of requirements of you that make engineering hard, but they also have tons of tools and libraries that make scale easy. In these environments, it makes sense to make even the most trivial systems horizontally scalable.
Conversely, if you do not have Google's or Amazon's distributed system components, and you don't have access to expertise with those tools, scale-out is likely the hardest problem to solve. GCP, AWS and others know this, so they charge you a lot to solve the scale-out problem for you (using their internal tools).
This is the source of the tension. FAANG-style engineering is what pads your resume (and establishes you as a "smart engineer" in the eyes of people who want to work at FAANGs), and simpler systems get things done until you absolutely need to scale out.