I think you could cut it off only if you are really interested in having that shorter length. Otherwise, you could get an inch or two cut off and that would seriously help repair your hair. Then go for more regular trims than you would normally do, or get a little more taken off than usual at each trim. When my hair was in terrible shape after not having a professional cut for a few years, I finally found a curl hair stylist who I trusted and she told me I could either chop it all off at once or come for trims every 8 weeks and it would be restored to healthy in about 6 months. I did the gradual method and it worked!
3a (with 3b) Fine texture/Normal porosity/Medium density
Low Poo (Aveda's damage remedy); Styling: Aveda's: Color Conserve Daily leave in+ Be Curly Style Prep+ Phomollient (mixed w/ Defining Whip)
Finishing: Aveda's Texturizing Creme or Defining Whip; Eufora Pure Polish Drops
Color Maintenance: Aveda's Madder Root condish+Clove condish