I don't even think the ones I bought were 4 years old. I think they first came out 4 years before, but were still selling them only a year or two before this happened. And it's completely ridiculous for hardware meant to automate things in your home.
For instance, I still have a bunch of their switches installed inside my walls around my house that I bought well before this whole debacle. When that inevitable security vulnerability pops up for those, it's going to be a huge pain in the ass to tear all of those out of my boxes and rewire new ones from another company. Stuff you install into your home should last longer than that. It's very expensive and time consuming to buy a dozen or two of these to install around your home.
I've been pretty happy with the Eve Energy switch that replaced the Belkin ones for my plug-in lamps. I hope they support them for a long time, but they also use Matter/Thread so I think they should be more inherently secure? Eve seems like a pretty good company with higher quality products. These switches never go offline like the WeMo ones and they click on and off with near imperceptible lag whereas the Belkin ones would take anywhere from 2 seconds to 10 seconds, if they were responding at all! They are also more compact. No reason to buy Belkin when better products exist on the market for comparable prices (often even cheaper, Belkin likes to cosplay as a premium brand) and Belkin has shown that they will not stand behind their products.