This. The idea that this will be abused is absurd. Speedclearing groups aren't going to take the time to /gg. It's faster to just kill it. My static does CMs which this won't even work with.
For people/groups that are learning, this will give them some breathing room to see the mechanics and hopefully not 1-shot die just because they didn't avoid the red circle. It is a massive time penalty for a party to wipe in raids. If anyone reading doesn't know, the boss resets completely in raids after a wipe. You have to do all the pre-event things for bosses like Dhuum all over again before he even stands up and you can begin hitting the actual boss. It takes a lot of pulls on a boss for you to begin noticing the mechanics. Hardstuck.gg has a great post and image showing all the information on your screen that you have to pay attention to inside a raid. Having a little bit of space to make mistakes can help you learn it better on each pull (or boss attempt).
I really like this and think it is a positive change and will hopefully lead to more people trying the content and wanting to progress in it. Every pull they do, they'll do a little bit better.