If you have kids, you might already know this answer.
To be 100% transparent is also assuming they will
2) Be able to take action regardless
Your kids don't know every detail that mom and dad. They do not yet have the experience, wisdom, discipline and mindset. They are loved, appreciated, cherished - but we massage the truth to help them work through it.
If you believe:
1) That fear influences imagination and people make decisions poorly.
2) That the grief process is always a consideration - we are all human. This human condition and the grief process does whack people out to do unusual things they later regret.
The five stages, denial, anger, bargaining, depression and acceptance are a part of the framework that makes up our learning to live with the one we lost. They are tools to help us frame and identify what we may be feeling. But they are not stops on some linear timeline in grief.
3) There are many times we trust others and take action BEFORE we truly understand why.
4) The staff does not have the mindset of "I am responsible" (Though you will have special leaders/linchpins who are critical to success)
You will probably not be as concerned about the difficult news - but more focused on communicating "The New Plan".
And - then we also must be careful of those wolves, cons, and people who are ready to do harm. They are on every staff, in the minority of course.
Some news/information can be used to make it worse for the employees you are hoping to be generous with (by being transparent). This might be the most critical issue of all.
After thousands of staff, "transparent" relative. There can be local transparency related to a person's role/responsibility - and there can be deep dive transparency that does nothing for the employee to learn of it.
It is important to remember that loose lips sink ships and everyone is now a publisher on media ready to share with the world. Which means that ensuring success of the team may require discretion.
What we share or hold in reserve to our kids, grandkids, family and loved ones - is based on love and caring.
Those who are responsible have a heavy burden - it is lonely at the top.
Disclaimer - This is not a hard and fast rule. Each team and scenario needs to be considered case by case. .