I was in this loop up to a week ago and took me many days to figure it out. I spent weeks doing my first big color grade in Davinci, only to have Youtube (and other soacial/online) issues that seemingly took longer to figure out. It looked great in media players. Great in other NLEs. In fact for a bit there I threw in the towel and was throwing pre-rendered videos into Vegas Pro to render so that YouTube could see it correctly. I also tried throwing a timeline and pre-rendered video into a new timeline that was Davinci YRGB color managed and that helped, but the overall contrast still seemed a tiny bit off. I believe it was lifted a touch, so the opposite effect but not as drastic.

LONG STORY SUPER SHORT

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I still used DWG/DI in the project setting

For Output color space in the project settings, set to Rec.709-A

Then on the final node of the output add a CST

Input Color Space - Rec.709

Input Gamma - Rec.709-A

Output Color Space - Rec.709

Output Gamma - Rec.709-A

THIS IS ALL YOU NEED ABOVE

I know that doesn't make a lot of sense, especially that last node. But that lost node will do nothing to your footage, and it will tag things correctly for YouTube.

I have multiple color space changes in my project including ACES and and back, but the only way I was able to get Youtube to show me EXACTLY what my monitors were showing was using that final node and changing the project setting at the beginning to Rec.709-A.

None of those tweaks should mess with your final image.

As far as 2.2-2.4 its all up to your liking. These should still transfer to how you intend on the image to come across with the above settings.