I'm in the same boat as you, for me it's security, l use my phone for everything, Samsung may bring out timely updates for the latest top end phone but after a couple of years don't really support them security wise as they should, and mid to lower end phones, basically are unsecure after couple of years
At least Google which l hate their phones by the way, are giving all their phones 6 years of regular monthly security updates with all security patches. All patches, every month for six years, samsung make the best phones but unfortunately if you can't afford a top end phone every two years from release date. Your taking unacceptable risks. I really wise samsung would concentrate on existing customers needs more, they now behave like an autistic child constantly moving on from one toy to another