No, they traded the #1 pick because
1. They knew they didn't know what they had in Fields or the offense due to lack of pieces around him
2. The QB crop was considered weak with heavily flawed prospects
3. They were able to obtain not only quality assets, but multiply those assets from one
4. This year's QB class is considered really strong with 2 guys who would go #1 in any draft who play the QB position
Offense changes when you have to bring the backup QB in, only if that team has contender aspirations. The Bears are not a contender. Heck, before JF showed us what he had this year, the Bears were considered a fringe playoff team at best. There's no reason to change the offense which means changing schemes, changing development work for the rest of the offense because a guy cannot process the field. And yes, offenses change when new coordinators come in. Why? Because the new coordinator knows how to run their offense, not something else. Getsy is not a new coordinator, he's trying to implement his philosophies. Just last year, he was getting praise and being talked up as a potential HC candidate down the line. Now, because Justin struggles, it's because Getsy suddenly forgot what offense is? That's ridiculous.
Martz, Getsy, Nagy, whether you like them or not, are professional OCs who all know that you have to be able to pass the ball in the NFL to win. Getsy and Nagy have struggled to get JF to read a field or throw with any anticipation.
What's nuts is wanting to change an offense for the 6th time in 10 years and blaming the OC as if the players to run the offense are enough. That's asinine to me.
Can't wait for next week's game asking the Bears to play "Bear football" and run the ball 100 times, then complain two weeks later when teams see it coming and they can't get more than 100 yards of total offense.