I'm probably overthinking this, but Resident Evil has Japanese devs and I heard Japan has a culture of not wanting to carry around more than you need. I wonder if the small inventory space in Resident Evil games is related to the cultural idea of packing light.
It has more to do with characters not being professional horror survivors at the start of the series and just going on routine missing person in the woods call, that later just became part of the games. Also there is no explanation in any game why don't they wear something a bit more protective later on.
The small inventory space is likely a technical limitation and/or a direct gameplay decision, rather than a cultural one.
I don't believe that any person, Japanese or not, would think that a special forces rescue team would take only the minimal supplies (with big risk of not having enough), and then being stranded at a new location and purposefully not stocking up on resources when the situation becomes obvious.