Maybe they mean with dependencies? There are some bloated libraries out there but because PHP is a dynamic language, the bloat only matters if it’s in your hot path.

But I would say a 20k line PHP app is pretty small… we probably have 20 different 1k+ files in our app. They’re not pretty but they’re still fast enough and they work so I’m not gonna try and rewrite them just for giggles.

That said, when working on this legacy behemoth, it’s not uncommon we find a way to delete a few hundred lines because there are so many old features that aren’t needed by the business anymore so we can remove that cognitive load from codebase. Maybe that had a similar experience and the rewrite was just a good time to get buy in from the business to admit that the features weren’t important anymore. We run an e-commerce site so there are lots of little marketing experiments cluttering the app and it’s a constant churn to remove old ones and add new ones for people to tweak and test with feature flags. Removing dead code is just a part of the job.