As someone who very recently finished his Ph.D. in CS and was working full-time as a software engineer at the same time, I must say that getting a Ph.D. is difficult and takes a lot of willpower and dedication. It's not easy. Some people will say this person wastes years learning about this particular obscure problem, some people say this person doesn't have industry experience. But after getting a PhD myself, I have a huge respect for anyone who has a PhD. It's not easy. Too many times 5 minutes before meeting my advisor I wanted to tell him I wanted to quit or take 1 year off. I was under immense mental pressure and was having similar thoughts because my parents thought I was close to finishing but I was not. I don't know this particular person but I feel the pain he went through.