Lot's of members here running 93-94 pound 37 inch toyos tires. I can't find any complaints on control or ride comfort.
I think you are drawing the wrong conclusion from the fact that nobody complains about the drawbacks of going big - probably because it's understood and the focus for the bigger tires are on different performance factors.
MPG, braking and acceleration are clearly and obviously suffering from more
Unsprung weight - potholes get a lot worse...Google it - lots of good info readily available - tire rack had a nice article on it if you want to get a basic understanding.
They're lighter. Kevlar belts.
I ran across a post here where a 35 Baja non project was weight in at 64lbs - would be surprised the 37" was much less than 75lbs
The 55lbs for the Baja earlier mentioned in this thread appears to be wrong.
Don't think Kevlar does much for sharp rocks - not sure about it - just don't think Kevlar vests do much for knifes.