Cotton is commodity, the price is determine by supply and demand.
Floods in Pakistan and heavy rains in China have drowned the cotton crop in that part of the word, causing the cotton price to skyrocket 56 percent in the past three months.
Your question whether price increase of cotton is ok, subjected to individual.
You can buy a cheap/no brand cotton shirt for 10+ bucks, but you can also buy an expensive branded shirt for few hundred bucks, so which is worth it? Ofcourse sometimes the material of branded shirts "can be better", is it worth the few hundred difference? End of the day is up to consumers choice.