Point A: Biggest wake up call for me going from a startup to big tech.
Point B: A year into a company, I'd be exaggerating if I said I knew more than 1% of the codebase. So many things the product needs to operate that users don't know exist since no one cares about what's under the hood.
Point C: Yep, imagine having users all around the world who enter and send personal data, and who might use assistive technology. At a startup, it was pretty normal to get the minimal amount done to address some of the needs (if at all) whereas at a bigger company there's way more effort to make sure it's done properly.