Different things will work for different people. I have quite a few Wi-Fi devices now, some thing I never would’ve expected several years ago, but they are almost all ones that work with homekit. Some, like the Meross, also work with smartthings.
For example, I just put up a project report this week about the meross RGBW table lamp, which we use for notifications. It’s a very simple and elegant solution at relatively low cost for things like an “on air“ notification for zoom meetings.
Meross RGBW Table Light for Notifications
I agree the smartthings platform requirement for custom code for certified zwave Devices is very frustrating for both customers and device manufacturers. 