It seems to me you're trying to turn a very isolated issue into a problem with the manufacturing process.
My own annextodayel evidence: While we don't use our phones naked, the bottoms are certainly open. We have a space gray 6s plus, a rose gold 6s and a space gray 6s. All look like the day e night them, and the rose gold gets tossed in my wife's purse with keys, etc multiple times a day.
As with any smartphone, these things are being produced in massive quantities. This just isn't likely to be some grand manufacturing flaw. If it was, I suspect a lot more people would be speaking up by now.