Can confirm this happens on multiple devices, both an iPhone and an iPad upgraded to iOS 17. On restart, WiFi simply fails to connect until it is manually disabled and re-enabled. It's specific to iOS 17, because an iPhone which still has iOS 16 does connect automatically to the same WiFi network on restart. And on the iOS 17 devices, this behavior only began after the devices were upgraded from iOS 16.
In fact, the Control Center will show the name of the network that the iPhone or iPad is trying to connect to, reading as though it's connected, but without a signal strength indicator where the WiFi signal strength should normally be, until WiFi is manually toggled off and on again. This is especially annoying for an iPhone that restarts overnight on its own, fails to connect to WiFi, and chews into cellular data allotment during the night.