A lot of people choose to ignore foreign language or non-English language films
Of course if American television and film actors took English elocution lessons then there'd be no need for sub-titles.
I practise my well-rounded vowel sounds and eschew mumbling to sound like this man whose diction was mistakenly thought to arise from speaking with a mouthful of other gentlemen.
3.10 to Yuma in the clip or watch the lot if you'd like a laugh:
I rely wholly on closed captioning/subtitling due to hearing issues. One little-spoken about issue is that sex scenes are ruined because the words invariably cover the good bits.