There will always be the need for Operational Research Scientists

 When I studied Operational Research, one of the two professors in the O.R. Department at the University of Lancaster was Professor Alan Mercer.  Anyone who knew Alan will know that he was in amazing character, and I am delighted that I co-authored one paper with him.  [https://doi.org/10.1057/jors.1978.188] (He wasn't my academic supervisor; I collaborated with him and his research associate Malcolm King on a project about the Church of England.)  

Alan had a fund of stories; someone had once asked him why there was still the need for O.R. scientists; if O.R. was such a powerful tool, why were there still unsolved problems?  His answer was that there will always be the need for O.R. in business, commerce, education and all areas of management, because new problems arise as a result of technological change, as a result of new industries, and as a result of twists to old problems, and (possibly most important of all) O.R. is needed to remind managers of techniques and results discovered years before.

Worldwide concern about Covid-19 has illustrated Alan's answer; there have been new problems identified across many sectors.  Stock control, disease modelling and monitoring, ward scheduling, supply chain analysis, distribution and queue models, and much else.  

Alan contributed work on location modelling, and distribution planning.  More than once, he lamented that his paper "The Churching of Urban England" (which explored models for location of facilities, in this case, churches, and which was published in the proceedings of the IFORS conference in 1969) was overlooked because other researchers didn't spot the relevance of such models to other location problems.

A recent paper in the Journal of the O.R. Society illustrates Alan's point about technological change and new industries.  Chunkmok Lee published "An exact algorithm for the electric-vehicle routing problem with nonlinear charge time"  [https://doi.org/10.1080/01605682.2020.1730250] .  New technology: electric vehicles.  New industry: home deliveries.  Twist to an old problem: location modelling of charging stations.  

That same issue of JORS (JORS 2021, vol 72, no 7 (July)) had other papers which illustrate the ongoing need for Operational Research.  Giuseppe Bruno and others look at the problem of collecting mail at a time when demand for postal services is declining[https://doi.org/10.1080/01605682.2020.1736446].  A.H. Kelte and others tackle the allocation of kindergarten spaces in Norway as the education system develops new constraints.[https://doi.org/10.1080/01605682.2020.1727786]   Both are old problems; both have new twists.  

So, O.R. Scientists - you will always be needed!