Sunspark it's comfortable if you're ok with keeping it at 95-100% brightness to avoid the PWM.
Have you considered Iris to lower the brightness without raising the PWM? I bought Iris Pro for my Mac. I am still in the testing phase, so I cannot yet say much.
On my phone I moved from my usual ~50% brightness level to 100% - which has always driven me nuts, and downloaded Iris Mini. It definitely changes the color temperature killing some blue light, but I have not understood whether it also reduces the brightness without introducing PWM. It is a basic app, just on or off. No settings to play with (I may try the full version. It is only 8 bucks once forever).
My eyestrain and headaches have gone sky-high. I need to do something, although to be honest I have no clue about what is going on. My phone experience was great until last May, and I always used 50% brightness, so, I bet, plenty of PWM...I have been wondering whether the display has deteriorated, but what is the chance that both the phone's and Mac's screens stopped working properly within months? I wish I had not unwillingly carried out some updates (downgrades) :-(