IMHO Get into fiber. It’s where any serious telecom companies are going. Copper & Coaxial are all but done. The only ones holding out are still using it because they are either not willing or can’t build a new Fiber OSP. 10 years from now, very few copper or coaxial OSP will exist.
But if the money is really that good and they don’t bill you back though no fault of your own (ie unrepairable OSP, etc.) then who I’m I to tell you not to take the job for a year or two.