4K Blurays you'll get HDR but not on standard HD blu rays.
if you are streaming then you can get HDR at 1080p. i don't know about other services but i pay for Netflix Premium (since getting an LG CX) and when I watch on my iPad/iPhone there is HDR even though it's limited to 1080p. even though the ipad has a 2388x1668 resolution and iphone has 2532x1170 Netflix will only stream in 1080p but the HDR is still there. not sure if Disney+/Prime, etc have HDR for 1080p movies. haven't tried them out yet on my Ipad but yeah they definitely support HDR. i use Netflix, Prime, Disney, Apple TV, BBC iPlayer and they all have HDR movies/shows.
Is there a way to tell which movies are HDR enabled in streaming apps? Like in HBO Max for example, it lists Ready Player One and The Fast and the Furious as both ‘HD” but The Fast and the Furious obviously doesn’t look as good.
netflix will tell you. on my TV it uses Dolby Vision and when you look at a movie/show listing it should have the Dolby Vision logo beside it. not too sure about Disney/Prime but the only other one i know off the top of my head that shows is Apple TV.