Because one has a hard deadline of late August to have enough resources for all children to be remote learning, and the other doesn't. If you are responsible for planning out the next year have another 2-4 weeks to procure what you need, or if the difference between getting them all now on short notice or four weeks from now is a sizable difference in money that your budget can't easily sustain, your decisions are going to be affected by that.
I imagine almost all the people planning this had very little practical experience with remote learning before this, and so had to learn about what it could and could not do well and implement a program to get all these resources to children.
That's something that many people here might be comfortable with, so I can understand why they may think this is the easy part, but let's flip this on it's head. How many people here, if instead of working out a digital solution and delivering to people were asked to work out a solution to have hundreds to thousands of children come in to a physical location, group into assigned categories for teaching, go to their individual rooms in these groups, and receive instruction for hours at a time with periods of play and lunch interspersed?
All the problems you might encounter in that scenario has equivalents for someone migrating from managing a fully in-person based teaching system to a fully, or even partially digital one. Whereas I might have problems knowing how to direct people as they arrive to the correct location effectively and efficiently, in a digital system they need to know how to find the students that are completely list in connecting to the classroom and never show up. Where I might struggle in making sure I had the appropriate staff at the correct locations to teach, they might struggle with the fact that not all students have digital accounts set up needed to connect (and not all parents are responsive to any contact during the summer).
Managing adults where you have a clear channel of communication to them that they are expected to pay attention to because it's their job is hard. I can only imagine what it's like to add a bunch of children in the mix (because you really are dealing with kids AND their parents) and have a sizable portion of the adults likely think "it will work out because it's their job, I'll just pay attention a couple days before school starts and do what they say, it's always worked out before".
I know I didn't want to read all the school emails coming to me over the summer (which reading between the lines mostly seemed to amount to "we're totally screwed but trying our best and we really hope school will be open because we have no idea how to do anything that we might need to".