Speaking as someone who has used both: yes. OBS is a general-purpose recording/streaming system. It gives you a lot of flexibility, but it can take some work to make things look "nice."

Screen Studio (and so OpenScreen as well) are "opinionated" and are designed to create aesthetic videos with minimal configuration. They can't do a lot of the things that OBS can do, but if all you want is to record your desktop with a webcam overlay, it's a lot easier.

OBS is more focused on live-streaming, even if it can be general purpose.

OpenScreen is more about screen recording, once recorded it turns into a simple-ish NLE that is focused on editing screen-casts.

Yes. For me personally, I am only interested in creating short demo videos in as little time as possible. OBS is an advanced software that requires me to learn to use it.

I just downloaded this and had a zoom effect video from the first attempt. The learning curve is roughly zero.

It's the automatic zooming animations. I've not found any OBS scripts that can do this?

OBS + kdenlive can also get you here, but this product is meant to be purpose-built and time-saving specifically for the computer instructions use case