If there is anything I want to keep, I will usually take notes but sometimes I cut the small part I need and store it in a special folder. I just wipe once in a while the main "obs" directory, every other week or so. if I haven't felt the need to play back a video, I doubt it will in the future so I don't keep a lot of retention, it is pretty much only to help me when I am getting distracted or multitasking during a meeting. Most of the time when I feel the need to play back the video, it is immediately after the meeting because I know something important had been said but wasn't 100% focused and want to be sure I haven't missed anything.

But I don't have lots of meeting, a handful a week usually. I don't need special hardware, obs seems to be heavily multithreaded. It might hurt the battery usage if I am not plugged but no core is going very high in term of cpu and I don't feel any slowness. I am recording in the 2500/160kbps veryfast(medium CPU usage, standard quality) setting at 1080p, it takes like 1MB every 3 seconds.

The process is exactly like that of streaming a computer game along with local microphone audio, except one pushes the "Start Recording" button instead of the "Start Streaming" button inside of OBS. There's got to be a million (or more) howtos written on the subject.

Hardware-wise, it's pretty straight forward: GPUs (including the ones that are a part of most non-Xeon Intel CPUs) have been up to the task of realtime video compression for around a decade or maybe more, which allows for the heavy lifting to be done in specialized silicon.

A bigger concern than the technical practicality might be legal concerns that generally surround audio recording.

For instance: In my state, I am permitted to record any conversation that I am a participant in -- I don't need permission from anyone but myself, and I don't need to notify anyone.

But in the US alone, there's also 49 other states worth of laws on the subject, and they can vary quite a lot.