Does the GM always have to chose system?

Hi dear folks!

I'm running into a bit of a chicken and egg problem. I want my players to create character goals so I can build my campaign around them. But they want a world first so they can create goals that make sense.

If we had a default system like 5e, this would be easier because there’d be some built-in setting expectations. But we haven’t picked a system yet, which means there’s a high risk of people coming up with character concepts that don’t work well together - leading to frustration.

Do I as the GM need to pick the system before Session 0 to narrow their creative space and help align the group? Do I need any other restrictions before I let the brainstorm? I’d rather not, as I want them to be proactive and tell me what they want - and I'm rather setting agnostic. But I also don't want another campaign where the character and campaign goals are misallinged. I'm feeling a bit... pressed. I want this to be collaborative. And my players are great - they want to be collaborative. I just don't know how to involve them.

Do you have a good process for handling this?

PS. I'm happy for system recommendations with set up too, if it's 2 pages max. We have played DW before, and it had great set up questions. I loved it. But I feel we have played 2-3 DW campaigns now and need something different. But our group is too busy to read something too long.