They're absolutely a contender. A few things are happening for them, first, Jordan Poole has become a nice player and will be a very good bench player and Otto Porter (a move I loved) is legit another great bench player. Their bench is really good. Second, the West is sort of falling apart. If MPJ can't take another step, Denver's sunk. Clippers without Kawhi? Nice story, but done. Lakers look like the Titanic, but it's still very early and if history has taught us anything, it's teams like this typically take until Jan or Feb to figure it out. Portland? Dame is in a huge slump. Where the west looked really stout a year ago or even 6 months ago, it's not nearly the cage match it looked it may be this year.
Now GSW has some dudes who are just off to a hot start and will regress to the mean (watch Dray's, Otto and Bjelica's shooting percentages), but they're absolutely a team who need to reckoned with. Give the front office some kudos for some really nice pickups. And all of this is with no Klay and their two superstar draft picks from the last drafts contributing nothing. It's a SSS right now, but they have a ton to be encouraged by. If by say, the ASB, they're still in the top 2, with starting to integrate Klay by then, they'll be someone nobody wants to play.