Netflix provides the best PQ & AQ comparitively. Hotstar is fair. Zee5 is disappointing. Even I have Zee5 subscription, I went the other way to watch RRR during its premiere.
I don't think anyone has perfect encoding as of yet... Netflix, the costliest and more advanced of them all doesn't get the dark frames any good... You can see the grainy frames all over the place if you are watching in a dark room if they are HDR content then it becomes even worse.
For all you Film nerds and fans, this documentary is about the company that really changed the VFX industry forever and also gave birth to the computer animation films with Pixar as well...
Ps. The company is owned by Disney. They are the ones invented the Stagecraft as well which is widely used for Star Wars and Marvel even on Sitcoms like How I Met Your Father as well.