I'm an early career software engineer and am curious - why do people say working "at scale" like it's a good thing? Why is that desirable? What are you doing differently from someone who doesn't work "at scale"?
Someone who's dealt with websites at scale before is going to be able to skip the first 20 of that process, so if you're a startup dreaming to get big, you find someone that's worked "at scale" eg Amazon or Google to design and build your systems and avoid some pain points like the website going down because the system can't keep up.
The actual functionality is a very small part of software development.
Making it work within its constraints (memory/CPU/network/storage in the small scale, ability to handle peaks while maintaining uptime at a larger scale), as well as dealing with the "non-functionals" like AuthN/AuthZ, obervability, performance, etc is actually the "hard part".
Then add in business "non-functionals" like "minimize CapEx/OpEx", "meet external SLAs with measurable and reportable KPIs", "meet corporate and regulatory standards and requirements" etc.
All of that is much larger than the actual function being developed.
You have as much impact and are exposed to as much scale (maybe not in terms of TPS but in terms of data, etc.), but you usually have much lighter development processes and a much more frequent release cycle. Your ops will also be a lot lighter.