Essential skill - many teens learn to touch type by having a computer and messaging their friends… there are programs to learn to type - my kids mostly used Typing Tournament for about 3 months when they were about 11.
If your child has particularly poor fine motor skills, touch typing can be a useful pathway into independent writing.
Until high school, I have generally typed all my children's essays and longer writing. This provides me with the freedom to quickly type what they dictate (I can type faster than I write). We can then read back through what they said, and edit easily.