If you're committed to the Mac system there is a combination of Mac and editing program that I think would be up your alley... and you won't have to buy a used Mac: Davinci Resolve 17 and the Mac Mini
M1 (I just saw that
@brett8883 just recommended this same Mac).
Davinci Resolve 17
Mac Mini- Apple
It may sound crazy, but Davinci Resolve 17 has a full featured editor that you can download and use FOR FREE, unlimited! They do have a "studio" version for $300, but the free version has 90% of the features of the$300 version which just expands its capabilities. The Mac Mini starts at $700. And for some crazy reason Davinci Resolve is optimized for this cheap little computer. So you can have a full editing setup, with monitor for possibly under $1000!
There are thousands of great tutorials for Davini Resolve on YouTube in small bite-sized lessons so you can learn it piece by piece. I'd never really edited digital video before, and started around July 1st. By July 15th I had completed my first project with just the basics, but still not terrible (shot with my
Mini 1). Just to show you what can be learned and accomplished from ground zero in just a couple of weeks (new to drones too!), here is a link to that first video...
First video project