Home device ROI

When I replaced the wifi gateway I had not expected client devices to fail. The first warning was that the Brother printer had issues. To solve those I needed to lower the wifi security level -- not a great solultion -- and it still drifts on and off the network. Yesterday I discovered that my Kindle Paperwhite (10th generation) will not connect. I obviously don't use it much, but did want to use it sometimes. I still use daily an iPhone 6 Plus, but I worry its connectivity to will soon end. I need to revisit my lastingness expectations for devices. Is 5 years too much to hope for? What should be the ROI on a typical home device combination of gateway, phone, laptop, tablet, printer, console, and TV? (The total cost for these spread over 5 years is about $100/month. Wish I hadn't done that calculation.)

Update: Installing the router's firmware update fixed the connectivity issues for both the printer and the Kindle. I hate to admit it, but I suspect the real fix was just the hard restart. Support 101.