Is this build good for a living room gaming PC?

I’m looking to build a PC for the living room so I can play games. I found [https://pcpartpicker.com/b/QFmrxr] (this) and thought it might be good. I do have a couple questions though. The creator says the motherboard or cooler should maybe be switched out for a better fit. If anyone knows a replacement that would work, I’d love to hear it. I was also wondering if I should go with Windows, or if SteamOS could be a better options, since I really enjoy the Steam Deck. Beyond that, if anyone has any tips or comments that could make my build better, I’d really appreciate it.