I think a lot will depend on where you think oakland finishes in the standings.
Sure, both Tua and Hebert look like top prospects right now but you may need a top 2, or a top 3 pick to land one of them. Is it a really strong rookie draft for QB after those two guys? Gruden doesn't seem like a "tank for...." type of guy even if that was the right play here. It's possible he went out and gave Antonio Brown all that money to finish with one of the worst two records in the NFL, but it just doesn't make much sense to me. I also think RB and S are the types of positions you draft if you are looking for an immediate impact. Not only do Antonio Brown, Josh Jacobs, and Trent Brown instantly make Carr look like a better player overnight but I find it difficult to believe the team doesn't win an extra game or two at a minimum. Let's say they win 6 games in 2019. In the last draft that would mean they draft somewhere between pick #8-#12. Some people may argue that Gruden might be willing to trade a draft(or several) high picks to move up and that might be the case. But I don't think Mayock trades away a ton of picks and he has a big voice in how they draft.
This looks like an Eli Manning situation to me, only Carr is about a decade younger than Eli. Last year everyone was high on Barkley, OBJ, Engram and even Sheppard. But they were down on Eli so he was drafted as QB22. Half of those guys under-performed and Eli still finished QB16. This year most people think Jacobs is a big improvement to the backfield(that already has a good proven receiver in Richard), and Jordy Nelson/Seth Roberts(the raiders #1 and #2 WR's last season..... no, seriously) were replaced by Antonio Brown and Tyrell Williams. That seems like a pretty huge upgrade to me. Carr is going off the board as QB23 this year. If his weapons actually stay healthy(unlike Eli last season) I wouldn't be shocked if he finished in the top half of NFL QB's. If you are in a vanilla 12 team redraft league that probably doesn't matter all that much unless your starter gets hurt. But in deeper leagues, QB flex, or dynasty leagues(where a lot of those top 12 QB's are in their mid to late 30's) it definitely matters. I don't think Carr is out of a job in '19 even if he doesn't play in oakland just bases on the ages of starting QB's around the NFL. While it's fun to watch Jackson/Allen run around and score fantasy points do we know yet whether they can throw the ball accurately enough to remains starters in the NFL? Murray seems like a great prospect.... would it really shock anyone to see ARZ draft a QB and it didn't work out? Bottom line, I just think Carr is one of the top 32 quarterbacks and is still in his 20's(he just turned 28).
If anything, I am a "buy" on Carr this year. But admittedly, a lot of that is because the price is so low right now.