Will the engineers also be responsible? I don't see how any attribution of blame can work in a system where causes are very distributed, such as in any large corporation. There is no one person responsible and claiming there is would just lead to a different sort of injustice.
No solution will ever be perfect. But the present day one clearly does not work, it leads to endless games of externalization and avoidance of eventual responsibility.
I've seen up close what even a little bit of accountability can do to large organizations, something a bit stronger would surely still have a positive effect.
As for whether the engineers will also be responsible: REAL engineers already carry responsibility and do so without any problem at all because they know their fellow engineers would not do any different. Professional integrity that's called. Software does not even come close to those standards, nor does most of tech.
And aviation - supposed to be different - went downhill in a hurry in the last decade and a half, not too late to turn back, though for Boeing it may very well be too late to recover their reputation.
