The way I see it; a story (movie, book, etc.) can only be judged by what came before it. Therefore I don’t think ANH can be judged in relation to ROTS, but ROTS is definetely informed by ANH and the OT. F.ex; a comic story set during ANH published after the PT is obviously affected by both the OT, the PT, and the EU so far.

I guess movies (especially the OT) exist in two (technically three) continuities;
Simply as a film only affected by any previous films (if any),
or as it exists retroactively as a part of the larger EU(s).