Well, I wouldn't sue them. I'm not into that sort of thing but I have seen lawsuits for less like the class action against Madden by 2K sports which worked or the class action against Ticketmaster. I am trying to be on Apple's side in any and all ways.
I have 6 or 8 UHD discs and somewhere around 230 4K iTunes movies. The ATV4K has been pretty much everything I could want but the way stuff dis-appears does leave at least a little room for improvement.
Recently I had problems with my Marvel movies. Looking into my purchase history I redeemed some of those back in 2012. There were distributed by Paramount and how they have Marvel listed as the studio but seem to fall under Disney's umbrella.
I re bought Captain America and Thor. I may re-buy Iron Man 2.... That one still shows up in my library but I can't stream it to my phone and in the store it shows up to buy or rent not as owned.
I mention this because it brought to my attention many of the movies I enjoy the most are the ones studios want to repackage over and over and over again. When this results in a better product (as it usually does) it helps take the sting out of it.
In iTunes I was quick to put favorites - Bond, Star Wars, Terminator, While these movies may not be the BEST movies they are the funnest movies so I continue to adore them. At least I still have Blu Rays of the stuff if I get tired of rebuying it.