[qikInNdOutReply]

Cultural change - you need to introduce a engineering culture, which happens to appear when people discuss a projects internal in peaceful code-reviews, contract-first (not into too much depth). You need to encourage a culture of engineering conversations, which also means that you need to kick everyone politicizing those conversation from the conversation. Project leads, scrum masters, etc. are out of the door for this.

They need to loose the fear of talking about the techstack with one another, which also means that somebody has to embarass themselves publicly and repeatetly to take that fear. Code-review your own repository first and talk openly about your mistakes. Remove the "smartest man in the building" dick measuring contest. Make it a habbit, that everyones code repository can be "visited" by the whole team. Make those visits constructive and something people will look forward too and even collect "large scale problems" for.

Actually manage this instead of just managing.

Also if your projects grind, do not expect smart people. Grind turns every great hire into an idiot, which then again turns every project into grind.