RAII is an exceptionally well done memory management model that some languages, like C++ and Rust, use to handle memory and it works exceptionally well. Hell even reference counting in Objective-C is pretty good. Garbage Collection adds a lot of overhead but gives you a good amount of safety and speed in development but you certainly wouldn't want to use it in a scenario that requires something done in real time or many types of embedded systems.

Honestly I wish more things embraced RAII. It seems like it would be a better thing to do, in the long run, but that's just my opinion.

Depends on how you build your application. Small focused processes work great. If you're not careful, and all the functionality gets stuck in one huge executable, it's possible to have long pauses. If that one huge executable winds up interacting with a serial device, like an old printer, or dumb terminal, well buffers are small. data gets lost. you have to resync and it sucks.

FWIW, my experience with that stuff is with java perhaps a decade ago. It can all be made to work with smaller heaps, better partitioning, but you wind up introducing more, but bigger buffers.

It almost never matters. Right up until you have to read the status from some old microscope, or something equally obscure.