For me, I do a mix of both. If I know I’m going to watch something multiple times, or want to save it for later I’ll download it, if it’s just a show that I’m casually watching in the background, or I’m using my phone/tablet to kill time I’ll stream it. Also my internet isn’t amazing (starlink) so if I’m downloading an Xbox update or something I can’t always stream 4K content without it buffering, so a lot of time I’ll go ahead and download something beforehand.
I like the fact that all options are equally easy.
Also, the cost of 6 months of RD is roughly equal to the price of a “value meal” at a fast food restaurant these days. Do you really feel bad about not having something to show for when you’re getting 6 months of all the shows you can stream for basically nothing? Especially when you have the option of downloading everything if you want. The entitlement there is a bit much.