Yes. the shake shingles with felt under layment is a poor roof from fire perspective and also on hail storm damage.
I remember the 1960’s construction my father was a residential and commercial contractor. I never remember him putting shake shingles on a roof. He was an excellent contractor/builder. (he was also a farmer, our family has owned/operated that since 1889)
My brother and I helped him beginning in our early teens, until I went to college.
What part of Texas?
Very good work ethic instilled, for you and your brother :)