in my experience, repo by "area" works the best. This usually means by team, but you don't want a team restructure to cause code relocation issues. And, yes, only when the org pressures push for it.
On the flip side, we have an org with 50+ teams and our operations team is pinning for a monorepo. They are just fine with one team's push forcing N teams to have an unexpected deploy and recycling of caches, connections, etc. Not to mention what will happen when team A doesn't have time to deal with team B's merge due to other org pressures.
On the flip side, we have an org with 50+ teams and our operations team is pinning for a monorepo. They are just fine with one team's push forcing N teams to have an unexpected deploy and recycling of caches, connections, etc. Not to mention what will happen when team A doesn't have time to deal with team B's merge due to other org pressures.