These conversations should usually start (and end) with "I love how Nuke handles this." As far as simplicity/elegance of the float implementation, coupled with speed.
Float is hard in AE. Render times spike, effects are still stuck in 16/8. Color management is complicated in AE. Or at least, relatively so.
When I teach this section of my AE college class, I try to hammer into the students the importance of planning - getting output specs in place from the start and letting that drive many of the decisions. Thinking in terms of acquisition, viewing and output. Taking the path of least resistance wherever possible. They definitely know how to properly work in float and settings to choose for usual srgb viewing and things like that, but they also know the cost involved and, to quote Kenny Rodgers, "know when to run." Staying 8 bit and keeping things simple can sometimes be a big sanity boost, all things considered.
For me personally, the extended gamut only comes into play when grading a feature that's cinema bound. In Resolve. Sometimes it makes sense to go ahead and flip into P3 vs rec709 for the color session, and change the monitors over and that whole dance. It's involved enough that I won't do it for dramas or like romcoms, but there was one recently that was kind of a Scott Pilgrim type of film, with lots of bright colors and clubby laser tag type of in-game scenes all shot raw, where I went ahead with a P3 native grade. I do think it made a difference and I could pick the p3 monitor vs srgb in a pepsi challenge situation. There are definitely colors not reproduceable, if the material is flashy enough.
But in the end, even if you've got the monitor firepower to work extended gamut, often times there's something to be said for just sticking in the same colorspace as your audience and making your decisions there, even if it is dumbed down from what you could potentially be looking at. Although, if you really want to impress a client or director and show colors the "other shops" don't... maybe you flip that switch to higher gamut, I don't know.
You know, those rec2020 "HDR" monitors are such a gimmick, but I can't help but think that it will be nice when everyone levels up and even the lowest denominator TVs can show a wider range. We'll realize how color challenged we once were.
