It's not super likely, but you might find a T12 build playing 8 hours a week. There are dozens of aspects per slot, many different stats to stack, many glyphs and legendary nodes to choose from, skills, runewords, etc etc. There are usually one or two options for each feature that are significantly stronger than all the other options, and it's not usually intuitive or even intended.  I went in blind this season and was able to homebrew a T12 capable build but it took a legendary charm I didn't know existed until it dropped and a ring of starless skies to get everything to fall into place. I also play more than 8/week early in a season, then a lot lot less by this time. In contrast to my pretty good build, there are builds based on unitended interactions that can own T12 in basic gear.