3. If a defender turns his back to a play, why does the offense get penalized for impeding their progress?
4. Did the NFL rescind PI's from coaches challenges?
Yes. It was a one year rule change that failed for two reasons. 1) without full-time reps and season long reviews of what uniformly constitutes subjective calls like PI and even holding in some cases, the variability of these calls is obscene. 2) the refs clearly HATED it and when they refused to overturn even blatantly missed calls, it became crystal clear that it was only putting a highlight on an issue they are unwilling to properly address... a big officiating issue with respect to the passing game in a passing league. So, rather than fix the issue, they simply turned off the spotlight.
5. Why are personal fouls not reviewable? In fights where both players are at fault, why only penalize one? Plays where a ref thinks there's a shot to the head that is actually a shoulder are wrong. So is missing a hit to the QB's head that gets missed.
While not reviewable, NY does already and has for a few years consulted with the on field crew to properly assess fighting penalties due to mandatory disqualifications.
Part of why refs want to not solely rely on review is that slow motion doesn't really capture the play as it happened in context. Also, a guy putting a shoulder to a guy's head on purpose is still a foul (see Vontaze Burfict's hit on Antonio Brown) and can still be a disqualifying offense as well as subject to suspension (as Burfict was, iirc)
As for the Refs missing head shots on QBs, no one knows. The Refs missed head shots on both Goff and Wilson in our last game with the Seahawks. Some QBs get calls even when it's close. I can't recall the last time Goff got a call for a head shot. I really don't wanna say much more than that as my blood pressure is rising just thinking about it.
6. Why are fans allowed in some stadiums and not others?
Game attendance is governed by local, state and federal laws. Some states and some localities have more stringent rules regarding gathering in public places and as such, there are no fans in some stadiums due to COVID restrictions. Unlike other countries, we're unique in our collection of states versus a homogenous country, so things for US citizens can be VERY different for them depending on the jurisdiction. That includes attending games.
7. Why isn't there a rule as to how loud noise can be piped in to distract an opposing offense?
Piping in crowd noise is illegal after teams were caught doing it to create an unfair advantage. After Paul Allen very smartly had the Seahawk stadium specifically designed to reflect noise back down onto the field and the building all by its lonesome created a statistical advantage, the NFL put in a rule preventing any further stadium enhancements that would specifically increase noise on the field.
Most of the crowd noise you hear on broadcasts now is like a laugh track... it's added to your feed, but it's not what the announcers or players hear and it's not piped in to the playing area.
8. Why do the Rams never play on Thanksgiving?
It used to be reserved for Dallas/Detroit, iirc and then expanded to include other teams. I think Dallas is the only team to always play on thanksgiving now and Detroit is a frequent player still. The Rams as a West Coast team likely don't play on Thanksgiving due to scheduling issues when they put the season together which is why you generally don't see anyone from either the NFC West or AFC West on turkey day.
9. Did the Rams change their colors to match Wal Mart's, or was it the other way around?
Actually, I think it had to do with television. If you look at those colors, they create the most contrast and thus 'pop' the most on digital TVs. (there's actually a lot of math on this, but that's not important here) Our blue is a very saturated blue which digital TVs produce very well. I think it was a genius marketing move to go with these colors even insofar as I lobbied for the old blue and whites because our Unis pop the most on TV.
10. Why is it called football when it's mostly played by your hands?
The same reason hot dogs come 10 to a pack and hot dog buns come 8 to a pack.
Hope I was helpful.