Hello @Stretch ans welcome to the community.
The reason for the 5-minute cool down is to mitigate server costs since they offer this for free, if you look in the roadmap they are currently working on a subscription format that would leave the free version (12-sec videos, 5-minute cool down) but also add some sort of pay service to lengthen videos and/or eliminate the 5-minute cool down. I have added a link below if you would like to see the discussion on that or add to it.
You can also add your ‘vote’ in the upper left of any items in the Roadmap or Wishlist you would like to see.