Almost always there will be less opportunities of that niche in the future; and it is probably difficult to get promoted (or build a career) on the basis of a t

Almost always there will be less opportunities of that niche in the future; and it is probably difficult to get promoted (or build a career) on the basis of a technology that will be replaced in the long run. Maybe if you have software project management skills (complex migrations from legacy tech X to modern Y), these might be transferable skills.