For True Tone: I always turn it off. I get the argument that a white piece of paper will look yellow in the right light, but a screen is not a piece of paper - it's a light source. Light sources don't do that, and so my brain notices something is off when light sources try to do that, because something is. I think my biggest issue with True Tone though is that I can't turn it on everywhere. So then some displays would have it and some wouldn't. And that would make it look even worse.
For Night Shift: There isn't clear evidence that disabling any particular range of blue light actually causes you to sleep better. I have by far the worst insomnia out of anyone I've ever met. For the past three days for example, I only managed to sleep 2 hours each day, from around 2am to 4am. The pattern will change randomly again beyond my control, or I'll just end up sleeping at completely different times each day for a while with no pattern at all. For the longest time I would wear "sleep glasses" at night that blocked blue light. The only thing it did for me was cause the worst depression I've ever had during times where I was awake mostly at night, and so I ended up getting rid of them. My mom used to use F.lux on her Windows computer but she gave up on that a long time ago.