Non-centrally controlled connectivity can be solved by low-altitude communication satellites[1], and other sky based solutions[2].
We should be focusing on tech that makes aerospace less costly. The benefits will extend beyond a free & open network. There is good science and theory on ways to reduce costs in aerospace, it's an engineering/business problem at this point.
How are LEO satellites not going to be centrally controlled? It's not like the satellite owners will let you use them for free or be controlled by commercial interests and subject to laws and regulations.
You are also not going to be deploying your own balloon Internet.
1. There can be multiple sets of satellite services an area. How many entities currently own satellites? Maybe 100. Reducing the cost will increase diversity in satellite ownership.
2. Satellites can, in theory, run a mesh network among themselves.
3. Decentralized doesn't mean you own one. Decentralized means there are multiple agents and none have a commanding control of the system. I don't need to be able to deploy my own internet balloon to belong to a decentralized system. Cheap internet balloons will allow smaller companies to work on the "last mile" problem, further decentralizing the network.
4. Decentralized doesn't mean free as in beer, free from commercial interests, or free from laws and regulations.
Satellites are expensive and frequencies are limited. Even if you solve the first, the latter isn't about to change.
Demand is also limited. Not a great combination, so your vision on multiple low cost satellite service providers isn't likely to come true.
There are only a few satellite owners you can buy broadband service from, not a 100. It's capital intensive and past bankruptcies don't bode well for new entrants.
Satellites can and do run satellite to satellite comms, a "mesh" if you like, but it increases latency.
Neither are balloons likely to be a viable long term solution.
You are also not going to be deploying your own balloon Internet.