A couple years ago I did some basic OBS recording of technical stuff and needed a simple, preferably OSS, editing and compositing solution polish up the vids.

The landscape was bonkers. After trying lots of free, freemium, and paid trials I finally landed on Kdenlive. At the time I got the sense that it had just recently, within the past couple(max) years, gotten much better and much more usable than a lot of the internet had caught on to. I'd liken it to the Blender 2.5 release. It was perfectly usable on my system for editing 4k video with my basic needs.

Haven't used it over the past couple years but it's nice to see that they have been pushing it forward even harder. Even based on my 2-3 year old experience with it I'd encourage anyone looking for basic, but comprehensive, video editing needs to give it a go.

Edit: I'm not saying it's limited to basic editing. I just mean that it's perfectly adequate and usable without being overwhelming and "unfriendly". Watch a Youtube Kdenlive 101 intro vid and you're good to go.