I use the free version of Monosnap to record short feature videos for poketto.me—the ones I post here, on X, and on Bluesky. It works great, but the default encoding produces videos that are far too large for other contexts—especially email.
Rather than fiddling with different encodings, I use the command-line tool ffmpeg to scale down the videos. A typical Mac screen recording often has dimensions well over 2000×1500 pixels—when half (or even a quarter) of that would easily do the job.
Here’s the command I use (courtesy of a friendly person on Stack Exchange)
ffmpeg -i input.mp4 -vf "scale=trunc(iw/4)*2:trunc(ih/4)*2" output.mp4