I see there are videos on youtube with 1080p resolution that are more than 10 minutes long and only 50-60 mb in size.
I have a video only 3 minutes long and only 720p resolution but unable to bring it down below 90mb in size.
I checked another answer here on reducing size.
Tried changing bitrate using
ffmpeg -i input.mp4 -b 1000000 output.mp4
ffmpeg -i input.mp4 -vcodec libx265 -crf 20 output.mp4
Tried changing -crf between 18 to 24, used both libx264,265 but it all resulted in nearly same output size, sometimes it even got bigger instead of smaller.