I'm not sure how you got this calculation. Suppose I'm considering a mortgage of 100K. If rates go from 1% to 2%, my payment goes from 322 to 370, an increase

I'm not sure how you got this calculation. Suppose I'm considering a mortgage of 100K. If rates go from 1% to 2%, my payment goes from 322 to 370, an increase of ~15%. If rates go from 6% to 12%, my payment goes from 600 to 1029, an increase of ~71.5%. Massive difference in terms of affordability.