Wow...as usually this topic fires up the responses...here is my 2 cents..
#1 Keep weight near CG and low...not hanging off either end...not really a "350 vs 150" truck size but balance or "polar moment' [loved that]...we have 6 ply tires and will soon switch to 10 ply...will put one of used 6 ply [lots of tread] up under the Tundra in OEM spare hanger...
#2 Valid assumption that we all use tubeless tires...therefore carry a plug kit, a good air compressor [Viair] and as a backup several large cans of compressed gas sealant fluid..oh, learn how to plug a tire before you have to...remember plug kits need to be rotated as they can dry out..
#3 Yes, 2=1 and 1=0 but for most of us two spares is just not in the cards..at some point we have to say enough is enough...no more weight or room available...that is why I like the suggested use of a tube and or tube/boot combo [will add a couple of boots to my off road motorcycle kits]...simple, light weight, low volume and will definitely be your "get out of jail free card" if you need a second spare but don't have one...rotate tubes, not expensive, and know that a torn sidewall may be beyond repair with a boot...but as Chris Scott suggests, you can literally sew the sidewall and then use boot [s]...whole different level of repair!
Self-sufficiency is mandatory for off road adventures and when travelling solo..but to a degree we are never completely self-sufficient.
Good discussion...thanks all.
Phil