After my Roku Express 4K+ upgraded to version 12.0.0 build 4184-CR it can take up to 2 minutes to automatically connect to my home network. If I walk though the network setup it connects immediately.
It is connecting to a 5ghz network running WPA2/WPA3 - Personal security. The connection is excellent.
58” Hisense 58R6+ Roku TV C232X
Roku Ultra and Express 4K+
Vizio SB3651N-H6 5.1 surround SoundBar