To do a postdoc because one could not find a job in industry after PhD is the worst thing. A post doc does not make you more attractive to an industrial employer (rare exceptions exist), and a post doc can be a really painful effort to get over before landing a university research position. If you equivocate already, that is an indicator that PhD may not be ideal. I'm not saying this is.
Broadly speaking, science and engineering doctorates are well respected in German industry and it greatly increases your chances of finding a job related to your given field. I studied a chemistry doctorate in Germany. All of my former colleagues landed well paid industry jobs very soon after graduating. I, however, returned home to the UK where I struggled to find any work related to.
Many of my friends with a PhD are in the same situation, except for those whom participated in industry internships during their PhD. I recently went to a conference full of UC Berkeley PhD students (Beyond Academia conference) concerned about how to get a job after graduation. I took away that personal connection is 85% important, matching keywords in job description (there is an algorithm.
Compared with a PhD, a job in industry will offer more immediate financial rewards, the chance of line management experience, and the opportunity to yield more tangible results more quickly.
I did my PhD in my fifties, after a computer science industry career. I am also a permanent resident alien. I can see two problems you are going to have that I avoided: I didn't start my PhD until after I had my retirement fund saved up, so my standard of living did not change. I continued in computer science, so my industry experience helped.
Don’t be paralysed into indecision by assuming that the first role you get after your PhD will define your career forever so you have to get it right. You can switch roles or industries as often as you want to. If it interests you now, go for it, give it a try. Your biggest enemy at the moment is not having much non-academic experience, so get some. Even if it doesn’t work out, you’ll be.
Regarding PhD will help you in industry to get job, its too tricky. It depends upon your PhD research area. as not all industry want to have PhD students. and with my interview experiences I realized very few companies prefer PhD students more then someone with a BSc or MSc. Companies are worried about PhD students as how the student after 3 years of research work will fit in industrial world.
Currently only around 55-65% of those who get jobs in industry after their PhD get research positions (suggesting it may have been better for them to enter industry directly). 13 Overall, only around half of computer science PhD’s get research positions immediately after their PhD’s whether this is in academia or in industry. 14.