There is no question about it. The 2019 Avalon will incorporate/be available with CarPlay starting in March. Toyota confirmed that already through multiple sources at the NAIA in Detroit. The Avalon (In all from levels) Will be the the first to incorporate it.
I'm not sure how clear I can be. Let's try this again. Until there's a physical car, available for purchase, with Car Play, I'm choosing to ignore Toyota's confirmations. Why? Because Toyota has said they'd incorporate it in the past. Mazda has been confirming CarPlay and Android Auto for a couple years now. Mazda won't be releasing the upcoming 6 refresh with either system. At the 2017 LA Auto Show, Mazda confirmed they'd bring one or both systems to their vehicles in 2018. Mazda is still ambiguous of when exactly and which models will get the third party system. Mazda also confirmed that Car Play was coming back in March. They were announced as a CarPlay partner back in July 2014, and have confirmed at least a dozen times since then they'd incorporate Car Play in the very near future.
And, for what it's worth, Entune is tied into Scout GPS (2017+ on Lexus), a Toyota and Telenav partnership creation; free for three years then requiring a paid sub. Car Play and Android Auto take over these native systems and work off of the phone. Toyota's hesitation has always been about privacy issues, which is a bit ironic considering they've entered in a partnership with Amazon to use Alexa in some of their vehicles that utilize Entune 3 and Enform 2 on the Lexus brand. Amazon is one of the least transparent companies when it comes to what they do with your data. Toyota also said four years ago that their first CarPlay systems won't come along until mid to late 2015. There's also no viable reason Toyota won't be offering the system on 2018+ Camry's when they use the same Entune software
I'm not sure if you've used the latest Entune or even Enform on Lexus vehicles, but it's slow and you can see motion lag while switching radio stations or moving through menus. There is no reason why a 2018 Lexus should have such a slow system. Only the LC comes with a slightly more robust system, but it's also a $100,000 Lexus.
The last time I went to the Lexus dealership for some minor maintenance, I had a look around the lot. I know of Scout GPS, but I was wondering what Lexus was doing. You can't project Google Maps onto the headunit. There's some workarounds with third party apps, but they're buggy. This was within the last five months. There were 2018 vehicles already on the lot.
Even Honda realized no one liked HondaLink and its associate app suite because it was trash. Though, both brands lose out on potential customers for not offering Android Auto. They're not exactly Porsche, who can say they only offer CarPlay because the majority of their customers own iPhones and not Androids, also similar in how they know most of their GT3 customers also happen to own Cayennes they use to tow their GT3 around.
Not to say CarPlay is better or worse than Android Auto. Apple Maps and Siri are awful, though. This isn't just a Toyota or Mazda issue. A lot of car marques have dragged their feet.
Edit: In short, until there's a vehicle on a lot that comes with CarPlay, Toyota can confirm up and down as Mazda and Toyota have for years.
The MY18's are putting down around 420, and the Gen 3 I/M is showing performance just about in between the Gen 2 (15-17) and a Gen 2 + GT350 IM/TB/tune, so I'd definitely not be surprised to see it do 435-440-ish rwhp and that is pretty stout (and well over 475).
