I've found that RAII and the stuff you have to buy into in order to use RAII come with more downsides than upsides once you scale beyond high level programs that try to get done a lot with very few lines.

> how plain C helps with this?

By staying out of the way and providing everything of what you actually need in the end. That is assuming a detail oriented approach where you deeply think about, and want to be flexible about, the organization of what your program should do. As programs grow into large architectures, and as programs get more performance conscious, they also get more detail oriented like that, and they tend to opt out of unflexible high level language features.